Akom's Tech Ruminations

110 Comments

1. Anonymous on 2009-05-01 19:46:

   Help, I'm trying to get a fridge compressor to power an airbrush, i can get the thing running then it cuts out when the 60 psi is reached in the tank ( pressure cut out switch wired to mains input., but it takes about 3 minutes before it will run again any ideas what is driving this, i think it may be the cooling time for the ptc? This is the only decent explanation of how the starter system works that i have found trawling the net and if it does turn out to be the ptc any ideas how to get around it? Tim

2. Admin on 2009-05-04 11:50:

   Fascinating idea. It may be the PTC, and if it is, I'd guess that a high power low ohm resistor on a momentary switch (across the PTC) would get it jump started every time... The problem is that you need both windings to start the compressor, and this is one way of doing it. However, I have another concern: I recall that A/C Compressors (at least automotive) use oil in the closed loop system for lubrication. Your system is not closed, and you most likely do not inject oil into your paint spray - so if I'm right, how do you lubricate the compressor?

3. Tim on 2009-05-04 18:54:

   HI Again, you're quite right the lubricant is a total loss system when operated like this, i use an air / oil seperator on the outlet to the airbrush, i also wonder if you need both windings, as in use the starter winding is used because the compressor is usually under load from the pressurised system containing the oil / refrigerant mix. THe lost oil is about an egg cup full evry three to 4 months so i can live with that. I have welded up a u shaped frame from scaffolding tube to act as a reciever to stop the pulsing and when pressure testing it with the fridge motor i was amazed to get it to 130psi and then i chickened out as my cut off valve is set to 50psi so i didn't need the extra pressure. I had thought of letting the intake air pull over the PTC to keep it's temp down and hopefully reduce the time between starts what do you think? The other option is that because the unit runs for less than 60 seconds each time to just let both windings run on and replace the motor every 12 months ors so, it was a scrap unit to start with so no financial loss. Best regards

   Tim

4. Jonathan on 2013-11-15 03:29:

   Please my freezer is not cooling as the compressor is not picking. It keeps making Clicking sounds at intervals without the copressor working. Could it be the Relay/Overload?

5. Homayoun on 2019-05-11 17:01:

   Hi - I have a Bosch fridge/freezer which behaves like the situation you were facing. There is a humming sound, clicks, cuts out on overload and then over and over again in circles. The compressor is not starting. I have checked the compressor on its own buy temporarily shorting the start and run connections and It starts no problem, I have bypassed the thermostat and have found the compressor is still clicking so the compressor and thermostat are okay. I have replaced the relay with a new one and the problem does not go away. I have applied the whole relay and and start connection to another compressor I have lying around and the independent compressor (which I am using for testing only) starts no problem. When the fridge is all connected up with its own start relay and connectors after the fridge has been disconnected for a while it starts only the first time. Subsequent to this when the fridge is cold and it stops the next run cycle exhibits the clicking symptom with the effect of the compressor failing to start. I am stumped what it is when the fridge only starts the first time and not subsequently. Please point me in the right direction as I have exhausted all my own knowledge! To state my problem in short all the separate parts of the fridge check out okay independently but when put together it only works once when the circuit is energised with power! Subsequent times are failures!! Please help. Thank you in advance.

6. AZZY on 2009-08-30 08:56:

   Why do guys like you write about things that they know nothing abou I quote "The PTC is a weird thing, it seems to be a temperature-sensitive conductor - when cold" and "I didn't bother to fully understand, I suspect it's about efficiency or not overdriving the motor when it's up to full speed."

   First plz bother to understand all then write about it.

7. Admin on 2009-09-22 18:57:

   Thanks for your opinion!

   The reason I write is twofold: 1) It's my blog. 2) I hope that someone more knowledgeable, such as yourself - possibly, would contribute with knowledge I failed to locate or include, it being - you know - a collaborative web thing and all. Imagine for a second that wikipedia waited to go live until all the articles were complete, perfect, and "full"?

8. Tim M on 2010-01-18 17:06:

   This was fascinating precisely because he didn't understand it yet. He is writing about the process of gaining understanding.

   This is true understanding, gained from experience, and from it we learn how to approach a new situation intelligently, not just to repeat what we've been taught. There is a world of difference between the ability to problem solve and the ability to follow directions.

   "It's this understanding of Quality as revealed by stuckness which so often makes self-taught mechanics so superior to institute trained men who have learned how to handle everything except a new situation." -Robert M. Pirsig Zen and the Art of Motorcycle Maintenance Ch. 24

9. Mike on 2011-12-10 15:59:

   This is perfect!! Thanks. I've already read many pages written by Professionals that say Make sure your door is closing properly then call a "qualified technician for repair" I'm about to go LEARN to fix this thing, and this guy just saved me a lot of time. And yes us Learning types often learn to fix stuff without learning the proper part names, or complete theory of operation. Sometimes you fix it before you learn everything - thats a good thing. KEEP SHARING!

10. Gary on 2009-09-07 14:16:

    Thanks, I just found a bad stop/start relay #3ARR65P4E3A6 on my MFI2568AEB maytag bottom freezer french doors refrigerator. My compressor OHM readings are 8.2ohms, 4.6ohms, and 4.2ohms. Refrigerator stopped cooling, lost all contents(BURRRRRP) haven't eaten so much in years LOL, but refrigerator shut completely off, sorta like a cut power cord. Found out that the unit somehow got locked out. After accessing the display modes, I was able to get everything up and running again except the compressor, it would kick on and hum for about 15 seconds, then would shut off, all coper line at room temp, evap at room temp and condensor at room temp. I'm glad I found this site, I will purchase a stop/start relay and see if that will fix the no cooling problem, thanx again, Gary

11. Jack on 2011-12-19 19:49:

    IThx for the info !! After the repairman came out and wanted $190 to fix our fridge I did some investigating....I got a new Start Relay Switch, hooked it up wrong and blew a fuse. Then I hooked it up correctly and the compressor ran !! then.. I opened up the broken part , the Start Relay box and inside I found a small broken ceramic disc...I rotated this disc and closed up the Relay Box. Then out this onto the fridge and it worked too !! So, what is this little Ceramic Disc, is it pzeio electric or just ceramic ? It looks to cost about 50 cents.

12. Trevor on 2014-07-11 00:52:

    Hey folks who are curious or tinkerers and what to try something cool with their fridge. I have been fixing appliances for the past 4 years as a profession and recently came across this great trick/tool to run your compressor completely independent of the rest of the entire refrigerator system.

    It will take a trip to your local electrical store and about $30 in parts but it is a fun tool to build and if you work on appliances regularly will be a valuable tool to have. Or if you are in a pinch and dont want all your food to spoil until you get a new relay and overload, you can build one of these.

    http://www.davesrepair.com/DIYhelp/DIYcompressortestcord.htm

    This tool powers up your compressor strait to the windings with a neutral and 2-hots. The second hot, which piggy backs from the first hot to a momentary SPST switch acts as your auxiliary power backup or capacitor, but only for a second when you let the momentary switch go it stops sending power to the compressor just like the capacitor does. Once the compressor is up and running it will continue to run until you turn this unit off. There is no relay or overload attached either. Just this home made compressor starter device attached directly to the winding terminals.

    I tried this today and it works great. It will help me in the field when I want to isolate the compressor to see how its running independent of the rest of the entire refrigerator. It can indicate restrictions or leaks if you pay close attention.

    Anyway check out the article if you are interested in building one. It took me about an hour and a half and I will use it when Im diagnosing customers appliances. And, I guess if you built one you could use it in a pinch as well.

    Cheers,

    Trevor

13. rich on 2009-05-29 11:36:

    The pressures on the compressor need to equalize before the compressor can start. It can't start against a high pressure, it might try, but will kick out on the overload. It may take 3 minutes for the pressures to equalize before it can start again. I don't think it is wise to try and paint with a fridge compressor, you'll get oil in the air. They are meant to run in a closed loop.

14. Rob on 2009-10-05 21:05:

    Sweet article, and much appreciated. My Jenn-Air JSD2695KES starting getting louder when the compressor is running a few months ago. Then in the last week or so, it started to get really loud and more frequent. I got home from an RV trip this past weekend to find my fridge and freezer at a balmy 55 degrees. I couldn't find much on the subject for a while, but kept digging, and eventually the part number listed in Gary's comment (3ARR65P4E3A6) is where I got a hit on this site. The Part Select dot com part number for this is PS2069971 (hopefully someone with the same issue will find this article and find what they need without as much digging as I had to do.)

    My compressor had the same symptoms of 10 or so seconds of buzzing, then stop. Repeat every 4 or so minutes.

    I checked the capacitor first thing, and it seemed ok, but it's hard to tell with just a digital ohm-meter. There seemed to be a bit of "deflection", and after testing it with the meter, there was about .4 volts of electricity on the capacitor that bled off as I checked it.

    The only other thing was the relay or the compressor. I'll go for the $40 fix first. My relay actually has the capacitor plugged directly into it, but after comparing it with your diagram, I found all the same parts and connections. I popped the rivet out of the middle of the relay and took it apart. Mine didn't seem to be damaged in any way (aside from a broken rivet). I had proper continuity between all the contacts you mentioned. The strange thing I did notice was that when I put an ohm meter across 1 and 2 in your diagram (without the capacitor or anything else plugged in to the relay), I got NO resistance at all for about 1 second, and then the resistance would climb to 5 ohm and stay. I don't have the equipment to try to put 120v across it to see if the resistance would go higher or not (well, aside from the open ends of an extension cord, but I wasn't that desperate). My only speculation is that either that little disk is not providing enough resistance, so the capacitor never charges, or with the 120v, it would resist too quickly and cut the circuit before the compressor could start. Or, maybe it is possible that the capacitor went out of spec enough to cause a problem, but not enough to look bad with an ohm meter test.

    I'm not electronics wiz by any means, and don't hardly know enough to be dangerous. Your article helped me greatly in solving my problem. Well, honestly, I was resigned to trying the new relay anyway, but your article made me a little more comfortable that I was making the right choice, and I just hate it when I can't understand a problem. To just replace the relay without knowing a little more about it would have left an emptiness in my heart.

    Thanks again for the write up!

15. mark on 2009-10-12 15:34:

    Thanks for the write up. I have a Maytag Dual cool and it stopped cooling and had the same symptoms of 10 or so seconds of buzzing, then stop. Repeat every 4 or so minutes.

    I took that back panel off of the fridge, disconnecte the plug from the compressor, checked the resitance and then put everything back together. The fridge is making just the normal sounds with no buzzing. Maybe it was just a loose or dirty connection. The fridge is starting to cool again.

    Thank you for the step by step.

16. Bob on 2009-12-16 17:22:

    Interesting write up; thank you. Since you requested additional clarity, should anyone have any to offer, let me provide a tad bit more.

    The PTC device, called various things... startup device... ptc relay... startup relay, and others... is known in the electronics field as a "thermistor", which is simply a contraction of "thermal resistor", meaning a resistor that changes it's properties (resistance) with heat, in this case, the heat generated by current passing through it. The PTC stands for Positive Temperature Coefficient, meaning that the resistance of the device INcreases as the applied voltage across it's terminals INcreases. A small applied voltage would provide a significantly smaller increase in resistance than would a larger voltage. That's not relevant here, as you might imagine, because the available voltages that are applied to this device for our purposes are essentially two... 0 v and 120 V. (FYI, there are such things as NTC devices which DEcrease in resistance as the applied voltage INcreases; we have no need to discuss them here, however.)

    You have correctly surmised that when cold, the measured resistance, using an ordinary digital meter, will be low (5 ohms to 25 ohms, typical), which is effectively a "short circuit" for this particular application. When voltage is applied to the compressor's run winding, it is also - due to the short circuit provided by the thermistor - applied simultaneously to the start winding. That's enough "umph" to get the compressor going, after which time the thermistor rapidly changes state from "short circuit" to "open circuit", depriving the start winding of any more direct application of voltage, since it's no longer needed to sustain the compressor. Remember, the initial inertia of getting the compressor moving against the "load" (compressed coolant) is much greater than what's necessary to keep it running once it's up to speed. Kinda like your car on a straight and level highway.

    These devices typically break apart as they deteriorate with time and use; you can often hear the pieces shaking around within the plastic enclosure as you move the enclosure rapidly back and forth. You won't hear this with a new one.

    Whatever you do, do NOT apply 120 V directly to both terminals of the device; it won't be happy. To test it, you may choose to put a 100 watt light bulb in series with it, then apply the 120 V to the thermistor/light bulb combo; if the thermistor is good (and it probably is if it's not in pieces), you should see the bulb light briefly and rapidly dim. However, in most cases of a defective thermistor, you'll know it's bad long before you need to do the light bulb test.

    As for the capacitor, I can't provide much additional input, other than to say that it is frequently not needed, though if provided by the manufacturer, by all means leave it in place. I suspect you'll find that the capacitor tends to outlive the thermistor, and will probably not need changing for most "the-refrigerator's-not-cooling!" emergencies.

    Hope this helps, and best wishes to all!

17. Jerome on 2010-02-16 02:29:

    How do I get the compressor to run manually? I bought a fridge with a broken computer control module and only want to run the compressor on a timer. I've pulled apart all the wiring I can get to; there's a digital display and a control module up on the top in the front. Near the compressor I can find the start module but I don't see a capacitor (not that I know what it would look like but I'm sure it's not small). I'd follow your advice and just short out the capacitor if I could find it but I'm afraid it might be part of the control module up top. Or I've read that some compressors don't need a capacitor. There must be a way to just put it on a timer and cycle it on and off.

18. Admin on 2010-02-16 09:41:

    I can't really advise you on a fridge I haven't personally hacked apart - I'm not even a refrigerator serviceman (I'm a programmer). You should be aware that I wasn't shorting the capacitor because I needed to short the capacitor. I needed to short from one compressor winding to the other, and the capacitor terminals were the most convenient place to do this (review the diagram to see what I mean: I was shorting A to B)

    If you don't understand the wiring of your unit (and it sounds more high-end and more complex than mine), your chances of making it better rather than worse are not too good (and I won't even bother warning your about your own safety). Try to find diagrams, or spend some time tracing wires with an ohmmeter (while every harness you can find is disconnected, this way you are testing wires and not circuits you may not even realize exist). You got this fridge as a cheap fixer-upper, I'm assuming, so instead of money you must be willing to invest some time.

    That said, if your fridge is behaving like mine (buzz, then shutdown), then there may be hope that this approach will work for you too. Review the troubleshooting steps above, there are a few and you only listed your findings on a couple. Does your compressor have two windings? Do they have the same resistance? Is one getting power and not the other on start? - etc, etc.

19. jerome on 2010-02-16 12:09:

    I spent the last couple of days ohming out the fridge chassis. It's got a multicolored digital display that mounts in the front of the door and another pcb concealed behind the trim at the top of the door opening. Removing the pcb, I checked the contacts (there are twenty or so) going back into the fridge and found a couple of points where I can get 240 volts (i'm in Europe). I examined the pcb and the display, reseated an ic but really can't make very much of it. The person I bought it from showed me a scorched section under the glass of the display and told me it wouldn't turn on the compressor. I can see the scorch but I can't see what component fried because of the glass sandwich over it. The display comes on but flickers and lots of the elements either don't come on or go on and off. I checked the pcb from the door opening and there are some clues there but it seems to me the key is just to use the wiring that comes up from the compressor and stick a simple switch in there.

    How complicated can this possibly be? There is a motor, it has start and run states and you have to trigger and control these. The device itself is rather simple, gotta be all the same voltage except for control functions between the boards. So at the end of the day, 120 volts (240 im my case) has to be sent to the motor with a little capacitor boost and then changed after the motor starts up. Isn't that right? If all the parts are in working order, cutting out the computer control should be pretty simple. Just apply 120 in the right place.

    Here's what I know about the wiring "down there." Three leads go from the wall plug to the components near the compressor. The ground is screwed into a bracket on the compressor. The incoming hot leads are blue and brown. The incoming blue ties into two more blues, one of those goes upstairs, the other goes to the capacitor. All the blues contact one of the pins on the compressor. On the brown side the lead simply ties to another going upstairs. There is a third brown that comes from the capacitor and goes directly to one of the pins on the compressor. So going upstairs are a blue and brown that are hot and coming back is thinner black that goes to the start relay on the compressor, which in its present state would pass the current to the third pin. It looks to me like this device will get hot quickly and break the circuit, so I suppose it's just used to get the compressor up to speed but once that goes off I don't see how the motor gets current any more.

    I am tempted to just throw 240 on the black lead but it makes no sense to bust the compressor on a bad guess. I can tell you a lot more about the circuit upstairs but it seems to me that has to be irrelevant. The thing just sends some kind of signal, probably 240v full blast, back to the area around the compressor via the black lead. Or maybe it sends ground back there, or the other side of the 240. Got any ideas?

20. Anonymous on 2010-02-16 15:39:

    "So going upstairs are a blue and brown that are hot and coming back is thinner black that goes to the start relay on the compressor..."

    Jerome-

    If, in fact, there are ONLY those 3 wires that go "upstairs", then the wires you want to short to start the compressor are the brown and the black. Obviously, you do NOT want to short the brown and the blue, as you will fry whatever device you use to short them, and quite possibly yourself, as well. I would probably disconnect the wires that run "upstairs" if I were you; they're only needed to run the control board, which is apparently non-functional anyway, and to light the bulb in the unit. The best and easiest way to do this is to simply pull the two halves of the Molex connector apart (assuming your refrigerator has a Molex connector, as the Admin's does).

    Be aware that you can KILL yourself quite easily in this process, so unless you know what you're doing around electricity, LEAVE IT ALONE!

    And finally, don't run the compressor too long. Try different ON times, starting with only a few minutes at a stretch, to see how much ON-time works for you. Running the compressor for too long will cause your refrigerator to over-cool, as well as over-stress the compressor.

    And by the way, just to be clear, I want to go on record as saying I think this is a bad plan. The control board is used for a number of functions, primarily to keep the refrigerator interior at the prescribed temperature regardless of how frequently or infrequently you open the door. Running the compressor from a timer -- rather than allowing it to be done by way of a new control board -- is a hit-or-miss proposition that, though it CAN work, will provide you a less-than-optimal device that will always be a thorn in your side. Not to mention a bit of a kluge. Nevertheless, if you absolutely insist, this should do it for you, but PLEASE turn OFF the power before doing any of this and BE VERY CAREFUL !!! I've been "bitten" by the electical "snake" a time or two and lived to tell about it; you might not be so lucky.

    Stay safe- Bob

21. Admin on 2010-02-16 16:18:

    To add to Bob's comment (all sound advice):

    In your situation I would probably try to wire up an (optionally programmable) thermostat to a big relay, and control the temperature that way. I'd try to find the simplest, even mechanical thermostat (simple contact closure) that goes down to the temperature you are interested in, obviously, and use it to flip on the relay. Back in the days when window air conditioners were all stupid (on/off) units, I wanted to do just that. Of course in your case you probably want to measure the freezer temperature, and not a lot of thermostats go that low - but you can probably find some parts made for that (maybe from something intended for something entirely different).

    Of course if you want to make it a science fair project, you can do this with an OOPic or a Basic Stamp, and write your own control code. They interface to 1-wire sensors very nicely (I use those at home), all fairly cheap equipment. You can then optimize your fridge using multiple temp sensors! (Is this getting out of hand yet?)

    That said, maybe the fried electronics aren't much more expensive to replace than buying the aforementioned parts

22. jerome on 2010-02-17 13:20:

    I took the plunge and connected brown to black, the compressor kicked on and I ran it for a couple hours without problems. But only freezer is cooling. The fridge was still warm after two hours.

    I noticed there is a bank of valves near the compressor that are attached to a wiring cable that goes back up to the pcb. I always supposed this was some kind of zone control but I hoped it wouldn't make any difference if I controlled it or not. But now I get the idea that I'll have to switch these valves on and off to get cooling to the right place. Has anyone got an idea about these valves? I suppose they run on low voltage dc and probably the default is "open." That means I'll have to put a transformer in and wire it to the valves.

23. jerome on 2010-02-17 10:27:

    I checked out continuity from the three leads going upstairs to the pcb. They come out on the same 11 contact edge connector with blue on the first connector, brown on the sixth connector and black on the 11th. Previously I had noted a relay on this pcb, its a NAIS JS1-12v and now I can see that the black on pin 11 goes to this relay.

    In previous testing I could also measure 240 (europe) between 1(blue) and 6 (brown) and between 6 (brown) and 11(black). But if the three prong connector to the compressor is unplugged and power is on, then no 240 between black and anything. I also checked resistance between the three pins on the compressor but they read near zero on my old analog voltmeter and that seems reasonable considering they are just windings.

    So it sounds like brown to black will produce current. But what about shutting down the start circuit? If I cross brown and black the compressor should try to start. But the relay is on the pcb. What I find below looks like maybe overload protection. It's a black circular device that is open from the side that sits up against the compressor. Inside I can see a disk lying inside the housing.

    I'm having trouble imagining how this device works. If the relay upstairs sends line a/c down to overload protection then it must be the run circuit otherwise it wouldn't shut down on overload. So how is the start circuit getting momentarily engaged here? How could it with only three leads going upstairs? Is the current from black to overload also being fed momentarily to the start circuit?

    And don't worry about me frying myself. As you can see, I don't plan to do very much before I understand how it should work.

24. Bob on 2010-02-17 17:27:

    Yes, I guess I forgot one thing; sorry.

    In the freezer compartment, there will be a 240VAC fan (120VAC in the U.S.) that is used to push cold freezer-compartment air over to the refrigerator side; that's how the refrigerator side gets cooled. That fan is controlled by a thermostat in the refrigerator compartment and a relay on a small control board. Here in the U.S., that control circuitry is often in the very top of the refrigerator compartment, hidden underneath the plastic housing that contains a light bulb or two plus the temperature slide-controls for the freezer and the refrigerator compartments.

    If you've disconnected the Molex connector as I suggested... then, OOPS! That fan will never get any voltage. Sorry about that! You can try reconnecting it and see if the fan now works. You'll be able to tell immediately when you open the freezer compartment door, as you'll be able to easily hear it if it's running. And if the refrigerator control circuitry I described above is calling for cold air, as it should if the refrigerator is warm, then it should most definitely be running, unless the control board is completely shot.

    If you still can't get the freezer compartment fan to run, then you will absolutely need to replace the control board anyway. Unless, of course, you want to try to put the fan motor on a timer, as well, and this sounds too damn complicated to me already.

    Are you sure you don't want to just go out and buy yourself a new control board? Or try taking the old one to an electronics shop and schmoozing the owner to fix it for you on the cheap? I'd be willing to bet it's a rather simple fix; it's usually NOT the solid state devices that burn up, but rather an inexpensive resistor that decides it's tired and gives up the ghost. In any case, I'd try that, if I were you, before I went too far down the road of completely re-engineering the unit's control circuitry. You're certainly free to do what you like, of course... After all, I do recognize that we all need a new project now and then to keep the old blood pumping, but this one sounds to me like the pain level is far to high and the gain is far too questionable.

    Whatever you do, though, STAY SAFE! (And you might want to keep a fire extinguisher nearby. )

    Regards, Bob

25. jerome on 2010-02-18 13:19:

    I disconnected the fan way back when I took out all the shelves and haven't hooked it back up because it's at the top of the fridge, not near the freezer. When I looked, I couldn't find any pathway back down to the freezer for it to be bringing back up cold air. Now I'm trying to find out how to control the valve I found near the compressor. It looks like a "Bitron bistable valve" I found in a refrigeration forum. But it should be a simple matter to make the fan work and see if that fixes the problem. I inspected the freezer compartment and there is no air pathway back to the fridge and there is no fan I can find. So I doubt hooking up the fan will do it.

    The bitron valve I found has a resistor soldered in across the two spades of the incoming wires. I don't remember how to read the resistance from the stripes but it is odd to find two spades soldered together with a resistor. I get the feeling this valve controls flow of coolant to the fridge versus freezer. If it's AC, as Bitron says in its catalog, I suppose putting 240 in it will shut off cooling to the freezer and direct it to the fridge. But first I'd like to hear if anyone knows something about this valve.

26. Bob on 2010-02-18 15:03:

    Well, I think I'm at the end of my expertise, Jerome. My experience does not include separate cooling coils for the refrigerator and freezer compartments, so if that's what your unit has, I'm pretty well at my limit.

    Good luck, my friend, and I hope you get the thing working to your satisfaction. Enjoy the project!

    Bob

27. Tim on 2010-02-21 22:14:

    .

    Jerome, Try this site: http://fixitnow.com/ It is the best site I have found. You can post things on the forum and get advice from all kinds of techs who are very knowledgeable. Some who have given advice for appliances across the pond.

    You can even download appliance manuals. If you post in the forums, there is a section to request appliance service manuals for your particular model. What is it by the way?

    Their forums are here: http://applianceguru.com/

    If you are wanting to run it without the the pcb, maybe this article on making a test cord would be of use: http://www.davesrepair.com/drsn/Aug06bi.htm http://applianceguru.com/attachment.php?id=3102

    If you start a thread there please post them here too, so we can follow them. You'll need to start separate threads in the kitchen appliance section and in the manuals request section.

    Avoid another site called appliance blog. If you read a few posts you'll find many people going out and buying the parts advised only to have them not fix the problem. You'll see an absence of any diagnosis on that site, and frequent use of the "parts changing monkey" approach.

    Tim

28. Rav Shar.. on 2010-04-03 10:13:

    Hello,

    Your diagrams and descriptions are really helpful to understand or clarify on what you may be thinking. Thanks for the effort.

29. Andrew P. on 2010-07-20 20:46:

    The reason for the P.T.C. (positive temperature coefficient) resistor is to momentarily engage a start capacitor in the motor circuit to provide additional phase shift and increased starting current. As you surmised, after a couple of seconds, the resistor heats up and its resistance goes way up, effectively disconnecting the starting capacitor from the circuit. This used to be done with mechanical relays, but they have the disadvantage of contacts that pit and burn over time, and eventually the contacts no longer provide starting current to the motor and the compressor motor doesn't start. P.T.C. starters were introduced as a more reliable alternative. Indeed, where mechanical starter relays might work for 5-10 years, barring an accident like you had, a P.T.C. starter can be expected to last the entire useful life of the refrigerator. Using a screwdriver to shunt a dead P.T.C. is a reasonable ploy; electric motors are rugged devices, and leaving the start capacitor in the circuit a few seconds longer isn't going to destroy the motor. In fact, the motor could withstand tens of seconds of this abuse, gradually warming up, and eventually tripping the thermal overload relay.

    Refrigerators use start and run capacitors, because they have two windings in the motor, running about 90 degrees out of phase. Ideally, you'd be getting two power feeds from your wall outlet, each 110 volts, but one feed delayed 90 degrees from the other. Unfortunately, the power utility doesn't supply any such service to residential customers, so a capacitor is inserted in series with one of the motor windings to provide the needed phase shift. The two out-of-phase currents in the windings create a rotating magnetic field, which in turn pulls the motor's rotor along and makes it spin! The run capacitor provides sufficient current in the secondary winding to keep the motor running once it is up to speed, but a second capacitor, the start capacitor, is switched in at the start to provide additional current and phase shift to get things going. (If you could physically grab the motor shaft, you could provide this start-assist torque with your bare hand, instead of using the start capacitor.) A cold P.T.C. will have a resistance of around 10 ohms, and that will go up to several hundred ohms after power is applied. That means the P.T.C. is always running warm and there is always a bit of current running through the start capacitor, even when the P.T.C. has "disconnected" it. That's alright, because the electrical engineer who designed the system allowed for it in the thermal and power budgets of the compressor motor.

    Why don't simple motors such as those on record turntables and room fans have capacitors? They are what are called "shaded pole motors". They have heavy copper wires embedded in the stator, called shorted turns, plus some gaps cut in the stator laminations, that provide a phase shifted magnetic field to start and run the motor. These motors are inexpensive, lacking a start capacitor and start relay, but they are electrically inefficient, have low starting torque and tend to run hot, making them unsuitable for devices such as refrigerators. Some of them feature a thermal fuse to protect against overload, but these fuses are generally not replaceable and the motor is scrap if the fuse ever opens due to overheating.

30. RonK on 2010-11-01 11:46:

    It might help someone else to know that I was able to open up the case on my Klixon 8EA series starter relay and found the disc inside was in small pieces. I dumped out all of the pieces and used the largest two chunks to connect the two sets of contacts. Now I have time to order the part online to save some money. (My local appliance shop wants $75 for it)

31. nirmalya on 2011-02-22 10:17:

    following this entry and replacing the PTC and Overload which cost 1$ each( i am from India) my refrigerator became ok. lot of thanks.

32. Asif on 2011-03-13 12:26:

    How can i start refrigerator compressor without relay overload

33. Admin on 2011-03-13 13:58:

    Starting compressor without overload protection: 1) Call an ambulance (you should do that first in case you're unconscious later) 2) Short the overload. 3) Plug the refrigerator in. 4) If you're still alive, report your findings.

34. pick on 2011-03-17 01:56:

    Wow, I came here to check if a referigator relay also acts like a delay so if the power goes on and off it delays the power supply to the compressor. I still do not have an answer to this but this post gave me goosebumps. Good writeup, considering ample warnings in the writeup. Thanks. Please reply if anybody has an answer to my question. Thanks.

35. Anonymous on 2011-05-23 00:11:

    Thanks, worked great and was able to diagnose that it was the relay.

36. Jagjit on 2011-05-24 21:11:

    Thank you very much for such a hellpful diagram.

37. Marton on 2011-07-02 18:29:

    Thanks for the tips, as well for fellow user RonK for the idea of using the biggest remaining parts from the disc. I thought the compressor was bad when I first noticed the failure. The story: ;ast night I heard clicking sounds from the kitchen every few minutes and didn't notice it was the fridge (Whirlpool ED5FTGXKT01)... Until I opened the freezer to pick up an ice cream bonbom: it was melted I took the starter unit apart and found the disc all in pieces inside. Does anyone have an idea on what can I use as replacement for it? I'm from Buenos Aires so I don't have a reliable place to find parts for USA refrigerators and if I buy the replacement online it will take 15-20 days and I need my fridge! Using the 2 biggest chunks of the disc, the compressor started running properly. After 3 or 4 minutes working I unplugged it and replugged after a few seconds... The compressor started moving back and forth but it won't start. It seems the chunks are small to keep up in such case. Being able to replace just the disc instead of the whole starter would be great. Thanks in advance for any tips!

    Marton

38. Tim M on 2011-07-06 15:42:

    You can't unplug a compressor and plug it right back in and have it run. The first time you plugged it in, it started doing it's job and compressing the freon into the tubes. The when you plugged it in the second time, pressure was already built up in the lines. Too much pressure for it to start against. You have to wait 15 minutes between cycles for it to start up again. That's why sometimes when the power blinks off for a second, people's refrigerators stop working.

    How is it you are running a 110 Volt Appliance in a 220 Volt country?

    The part you need I found here: http://www.pcappliancerepair.com/model.php?mn=ED5FTGXKT01&brand=WPL&man=&pid=195993&pmid=132129 You can use this: http://www.pcappliancerepair.com/part-detail.php?sku=4387835&brand=WPL or this: http://www.pcappliancerepair.com/part-detail.php?sku=8201786&brand=WPL

    Until you can get the correct one you could see if you can find a Hard Start HS410 or RCO410. Don't use it as a permanent fix though as they can start fires. Or you could wire in a light switch to the start winding like Akom did with the screwdriver. BE CAREFUL.

    Again, why do you have a 110 Volt appliance in Argentina. Are you on Solar Power with a 110V inverter?

39. Marton on 2011-07-07 10:41:

    I bought the refrigerator second hand from a family who lived in the States and brought it here when they moved. I use it with a 2000W 220-110V transformer. Only con: the transformer draws 25W constantly, even when the fridge is off... It even draws such power even with the fridge unplugged... So it is not like Energy-Star compliant... but it works I found a replacement for the thermistor, but it is rated for 220V. The guy from the repair shop told me it will work, but I prefer to order the original replacement just to keep the compressor running within its intended parameters. I assume that with the original replacement, the compressor should stand with the case of the power blinking off for a second, instead of rattling back and forth without starting. I mean it will stress the disc, but it should start properly. I prefer not to have the fridge working with the 2 chunks left from the disc, just in case such power blink occurs. Thanks for the follow up!

40. Tim M on 2011-07-07 17:37:

    . If you are talking about the start relay, the guy from the appliance place is probably right: it would work. Reading some of the comments from other techs, most will use some universal relay like those pictured here: http://fixitnow.com/wp/2005/12/01/refrigerator-warming-up-and-makes-an-occasional-clicking-noise/ The only one you wouldn't want to use LONG term is the Hard Start, because as the name implies, it fixes compressors that are dying and on their way to the junkyard. It buys you some time to shop for a new one. All the others would work fine.

    . If you look at this post http://applianceguru.com/forum1/23792.html appl.tech says he uses this kit 8201799 on ALL brands. I respect his and RegUS's opinions; they are very knowledgeable. The relays and overload protectors are pretty universal items, though I would check on this forum http://www.appliantology.org/ to be sure about using a 220V start relay on a 110V machine.

    . As for your fridge not getting going after unplugging and plugging it right back in can happen to any fridge. It overloads the compressor. Once it has started you cannot restart it for at least 10 minutes. If you unplug it when it has already been compressing, it will try to start under a full load and trip the overload protector until some of the freon works its way through the system, then it may get going again only to come up to a full load too quickly and trip the protector again. It may slowly warm up for days as it cools some but keeps overloading itself. When ever you unplug the fridge or shut off the breaker (while the compressor was running) leave it unplugged for 15 minutes, before starting it up again. Some refrigerators, particularly commercial ones have a delay built into them, so they don't get stuck like this.

41. Marton on 2011-07-08 01:15:

    Many thanks, Tim for the links and the info. I didn't post on appliantology.org (didn't know about the site until now). Where I did post was here: http://forum.appliancepartspros.com/refrigerator-freezer-repair/260840-compressors-starting-device-replacement.html#post481481 and I've been told not to try it because it would work out of spec. I'll take that for now

42. Troy on 2011-07-09 19:33:

    I just wanted to thank you. I had trouble with my fridge and knew nothing about the inner workings ( though have a better understanding of repair than the average homeowner and a willingness/desperation to figure things out ). I tried a couple of these various trouble shooting websites, most of which were so utterly basic they they weren't helpful at all "Is the trouble the overload capacitor? Replace it" or others which offered up plenty of options to try and even percentages of times the particular part fixed the problem.
    One suggested the Run Capacitor.. as it was a parts house, I tried it and was happy with how quick the part got here. Until I realized it wasn't the right part.
    I started searching again, and found this page. I thought it was the most informative one that I found... and despite deciding to not actually try the technique he suggested... It helped me understand the circuit and what everything does better than any other site. The knock on him "Why do guys like you write about things that they know nothing abou" as AZZY did, I couldn't agree with less. He wrote it from the perspective of someone trying to work it out, he never claimed to know everything and most importantly he helped me. Something that quite a few of the other links I found failed to do.

    As it turns out, after understanding the design better... I was pretty certain which part I was actually having the problem with... went in and fished it out... and called a local parts house. They told me they do not carry any capacitor/overload/start parts and instead have a universal replacement.
    I wouldn't have attempted that without having gotten my better understanding from this page.

    It worked... it took all of 25 minutes to replace from the time I left the parts counter until it was installed ( admittedly the old unit was already removed and the cover off ) and cost me a total of $38. ( not including the wasted $28 for the run capacitor I ordered online and the food that spoiled in the 2 days from when I ordered it and got it)

    Had I ordered the part already, I might well have attempted his round about to get the thing started... and then this might well have been an even more important post to me... but even without that, I am very thankful that he did put it up here.

43. Dan on 2011-07-12 20:04:

    Hello everyone,,,,,My frig started to turn on & off (cycle?) frequently. So, I've been searching for discussion about start/run problems with any top freezer/bottom frig units. My particular unit is a Magic Chef model RB214RF. It has the disk type start realy and another two prong overload. There was allot of dusty fuzz on the coils,,,cleaned them off, cleaned the fan blade and all remaining area under the frig. The "disk" in the start is not broken, show continuity across the opposite terminals (has 3), the overload show conintuity across it's two terminals. The compressor terminals (common-start/common-run/start-run) shows no ohms on my old digiital multimeter set on 1x/ohms or auto detect, I've read where that is good and that is bad,,,,not sure if my multimeter calibration could be off the small ohms stated (going to get a resistor of known amount and check it) that is supposed to be found across those terminals. Tested each compressor terminal for ground with compressor housing,,,,all good,,,no continuity.

    Having Nephrogenic Systemic Fibrosis, that about ended my ability,,,,so I called a service techinician. They come out an installed one of the 3N-1 devices. Compressor came on and run for about two hours, then stalled and will not start again at all,,,,made a humming/clicking sound, so I unplugged it.

    I have been searching for another used unit that I can afford, not easy in a rural area. I took off trhe 3N-1 device, gave it back to the techinician. Here is my questions:

    If my multitester is correct in reading 0 ohms across all terminals on the compressor, but no short to the housing,,,,is the compressor bad? Food is already spoiled and I'ml living out of a small chest freezer. If not, I want to wire it all back together with factory start relay/overload, but I didn't take a digital image of the wiring before the technician installed the 3N-1 device and he couldn't remember (or refused to tell me) the correct factory wiring to all devices.

    I don't know how to post an image. I have 2 blue wires & 1 orange wire tha comes down from the top of the frig. The fan has 2 black wires. The start relay has 3 terminals, the overload has 2 terminals and the run capacitor? mounted on the rail between the fan & compressor has 2 terminals. I'm sure the technician cut off one or more jumpers that may have gone from the capaciitor and the compressor. Can anyone lead me to a source/image of the correct wiring for thsi frig? The schematic on the back of the frig has been torn in the area showing the area described and there is no other diagrams taped to the unit.

    Thanks Dan

44. Tim M on 2011-07-13 01:34:

    Dan, OK, either your repair guy ain't too bright, or he thinks you ain't.

    First, though, what are you doing posting for repair advice here? This is a computer geek forum with one article on a particular issue. There are forums specifically on appliance repair; you'd do better there for advice.

    Now if your appliance guy put in a 3-in-1. He did it as a TEMPORARY fix for one of two reasons. One, he didn't have the proper relay, and put it in until he got a new one. Two, your compressor is DYING and using a 3-n-1Hard Start could eek out a little more life from it, between a few hours to a few months. Third option is he is a parts-changing-monkey and just threw in something and hoped it would work. Now if he was coming back with another part he should have told you he was. If it was a temporary fix he should have told you to go shopping for a new fridge.

    So, if the 3-n-1 Hard Start was the needed fix, it means your compressor is failing, which, unless your fridge cost $5,000, means it is cheaper and more practical to buy a new one. Read more about it in this post: applianceguru.com/forum1/11587.html which includes the Electrolux warning on the fires that they can cause if used long term: www.scribd.com/doc/21952748/Service-Flash-RF0613-Improper-Technician-Use-of-Hard-Start-Kits

    However, I would be shocked if your repair tech "couldn't remember" how to wire the start relays! They are all wired about the same. See the diagram at the top of this article. If you can't trace it out from that, don't undertake this kind of work. But DO SOME TESTS before you start swapping out parts. Maybe he just thought you couldn't be safely messing around with this without killing someone as he could certainly get the wiring diagram online.

    Refrigerator Repair Reference: fixitnow.com/wp/2007/11/29/the-complete-diy-refrigerator-repair-reference/

    What to Check on Warm Rerigerators: fixitnow.com/wp/2005/10/23/what-to-check-when-your-refrigerator-or-freezer-is-warming-up-refrigerator-warm-refrigerator-repair/

    What humm and click mean: fixitnow.com/wp/2005/12/01/refrigerator-warming-up-and-makes-an-occasional-clicking-noise/ a) Your start relay/ overload is fried. b) If your start relay/overload is OK (which it probably is with a new 3-n-1) your compressor is shot = time for a new fridge. It also describes how to check the compressor.

    General Refrigerator and Diagnostic Repair Guide: fixitnow.com/wp/2004/09/07/online-refrigerator-repair-manual/

    Diagnosing problems by frost patterns on the evaporator coils: fixitnow.com/wp/2011/02/25/how-to-troubleshoot-warm-refrigerator-problems-by-reading-the-evaporator-frost-pattern/

    Warm Refrigerator Trouble Flowchart: www.scribd.com/doc/39305150/Warm-Refrigerator-Troubleshooting-Flowchart

    Where to post for help where people are on hand to answer you: www.appliantology.org

    Where to find a general repair guide for all kinds of appliances: http://www.appliancerepair.net/apnet/?session=405538

    Bottom line is, he probably did what he could to keep it alive, but neglected to say it wouldn't last long. Chances are your compressor is a dead duck.

    Good luck, Tim

45. John W on 2011-07-15 13:54:

    I have a frigidaire side by side. The compressor only starts if I shake it when the relay is clicking on for the 10 second window. If I do not shake it it will click back off and recycle every couple of minutes. Bad compressor? Bad relay? Can a hard start relay help in this case?

46. Tim M on 2011-07-17 23:25:

    John W. EVERYTHING you would need to know to diagnose this is in my previous post. Please read through it, follow the links, and try it out.

    Tim

47. Paul F on 2011-09-12 17:50:

    I guess I'm really stuborn, tight, or stupid, or smart. Debate is still raging. Just had my 10 yr old Kitchenaid side by side quit cooling. After bouncing around the sites like this I dialed into the Starting Device. I knew I could buy one for $40 online. But my fridge is warm and my kids act like going with ice is hell. So I call an appliance repair place "Mr. Appliance". They tell me they'll come diagnose and fix. If I don't have them fix it, it's $65. So the tech shoes up, plugs it in and diagnoses the start device in 2 minutes, puts a test meter on it and confirms in 2 more minutes, replaces the start device in 5 minutes and the fridge is up and cooling. Price to fix.........drum roll...............$260.10. So after talking to him and office manager (nice lady), they would not budge on price and I told them to take off the part and leave. So it cost me $65 to find that out. I should have gambled and replace myself. I just ordered one for $39. So feel free to chime in and tell me if I'm a pain in the ass. I just don't think $220 for 20 minutes is very cool (pun intended). OK, so now that I have 2 days to wait for part, do I make the leap and do the self start jump across the capacitor? I'm inclined to bring up my mini fridge from the man cave. BTW, i think these posts are great.

48. Tim M on 2011-09-29 19:24:

    Paul F, . $260 sounds a bit steep. Depending on where you called him from. New York City is one thing, Youngstown Ohio is another. Did you call someone from your neighborhood or did they have a long trip to your house. Also if you called a service company instead of your local appliance guy, expect to a lot more! Everyone thinks plumbers and service guys make a bundle on these small calls. They don't. Pay is better if you are in one place all day.

    . Now if it was a local tech, think about how many calls one can make in a day. In a lot of the small business independent trades about half of your hours are billable. If the guy charged $60 for each billable hour, that means that now he brings in $30 for each hour worked. Half of that goes into overhead, so we're at $15/hr now. Then take an additional 15% off for self-employment taxes.

    . Now a lot of appliance techs charge $90 just to walk in the door. There's a reason for that. How many appliances do you think they can fix in a day? Four or five? So if it is four and each one really took twenty minutes for the fix, not including the driving time, the billing time, the time spent with you. That means they should only get paid for eighty minutes of their day, when all of it is spent working? That would mean that $80/day gross would be what they should get?

    . How much would it take to do it ourselves? A couple hours finding the solution online? Another hour or two doing the diagnosis? Time to order the part? Think we could do it the first time in under 3 hours? Probably not?

    . Yeah, $260 is very steep. But $65 to come in diagnose is a bargain. If he did four of those in a day and he worked for himself, he'd do better begging for handouts.

49. TX on 2011-09-29 13:41:

    Great help from Admin's diagnosis. Following your tips, I have fixed my Kenmore fridge by replacing the start relay kit. Thanks

50. Cameron on 2011-11-14 13:52:

    Thank you for your blog post. I have a Whirlpool side by side. I was having the same symptoms as you. Both fans were running and operating but the compressor wouldnt run. Every few minutes there would be a loud click in the back but nothing. I took out the relay and it rattled and little pieces of burnt metal fell out. $49 (I know I could have ordered it online and saved a few dollars but I need my refrigerator now) later I replaced the relay. I plugged it back in and voila it all started up. I put a thermometer in the freezer and it cooled it down right away. I went back in about an hour to check it and it stopped running. I checked the thermometer and it had gone up about 10 degrees. I was thinking it was time to go new refrigerator shopping then I remembered reading about the auto-defrost. I advanced the timer and voila once again the refrigerator came back to life. Figures my luck, just as I thought I had it fixed the timer for the autodefrost came on.

51. Ed on 2011-11-30 23:39:

    Hi,

    Have a Maytag fridge that stopped getting cold and I think the compressor is ok, per your sum-total test. I get 3.3-3.5 on one lead, 3.1-3.3 on the other and 6.2-6.3 on the combined. How much of a margin of error are we talking about between good and shorted? I know the run capacitor is OK per a VOM that had a capacitor check function.

    I hear a slight buzzing/humming from the back of the fridge, but it doesn't stop after 10-15 seconds and then wait 4 minutes before starting again. In my case, the humming goes for a bit and then it starts starting and stopping in like a 3-5 second interval.

    The noise is actually very low and I wasn't really sure if it was coming from the compressor at all. So I removed the molex connector from the condenser fan to hear if the compressor was making any noise. And it is. So, can the compressor be shorted and still make noise like it is running???

    Could it be that one leg is fine and the other is shorted? Is there a way to test each leg of the compressor? Give power to just one coil at a time, directly, not thru the PTC (to rule that out)? As a way to see that the compressor is still working for start and run coils?

    Could my problem still be the PTC or Overload?

52. Bob on 2011-12-01 18:48:

    You haven't mentioned checking the PTC, only the run capacitor. Have you checked the PTC with your VOM? It should read very low resistance when cold. It's normally wired such that the two windings are effectively connected together in parallel when cold. Once the compressor starts, the PTC rapidly heats up (due to the current passing through it) and increases in resistance, effectively disconnecting the start winding, leaving only the run winding connected.

    It sounds to me as if your run and start windings are good -- meaning NOT shorted -- and as if your PTC is open, i.e. high resistance, even when cold. You can try connecting the two windings -- run and start -- together briefly (2 or 3 seconds) using a screwdriver with an insulated handle, for example, to short the two terminals together, but be aware that you're dealing with potentially lethal voltages here and take the appropriate precautions. If you're not confident you can do this safely, I strongly recommend that you don't do it at all. Heavy rubber gloves would not be an unwise precaution. If shorting the two windings together causes the compressor to run -- you'll know by the fact that the freezer starts to cool down -- that will pretty much confirm for you that your PTC is defective and in need of replacement. Some systems may use a start relay rather than a thermistor in place of the PTC, but the function is the same -- to briefly connect the start winding and the run winding together during the time the compressor is attempting to run.

    Good luck!

53. Mike on 2011-12-10 16:48:

    Last weekend I came home to a completely thawed out freezer. After unplugging it and plugging it back in it began working again and worked fine all weekend. My wife and I work in a different town 2 hours away from home and stay there all week. We came home today to find that really bad smell. My heart sank, I think the compressors shot I told her, and I walked away thinking about the cost of a new side by side freezer.

    She went to the net and found your page - I think its the starter device she said - (You know what I was thinking don't you) Well she / You were right. On my Kenmore removing the old part took less time than moving the refridgerator. and most of that time was removing the cover. After reading your explanation I skipped all the VOM testing and went straight to opening the starter case. Inside - a broken and obviously burnt "coin" sized wafer.

    My only regret - repairclinic.com is located a mile away from my office. If I had read this last week I would have already had my part. Thanks so much.

    PS - after reading this page this repair can be done by a Novice, and the part is in the $50 range.

54. Chuck on 2011-12-31 22:09:

    I obtained a Whirlpool dishwasher motor that I plan to use for another project, possibly a buffer, sander, or maybe even a large ball mill. This motor did not come to me with the start relay and I would prefer not to buy one. My question being, is there a down side to having the run and start wires connected during operation or will this simply give me added torque at the expense of efficiency? Any help is greatly appreciated.

55. Anonymous on 2012-01-19 11:59:

    My freezer failed yesterday - it was doing the usual cyle on/off routine mentioned here. I've checked everything and it all looks good. I KNOW the fault lies with the start operation of the compressor, but I can't tell if the compressor is at fault or the PTC.

    I disconnected all the wiring from the compressor and attached a homemade switch-box that allowed me to do the start routine manually. Compressor ran fine.

    I wired a 100W bulb in series with the PTC, applied power, and the bulb illuminated for a split second then rapidly dimmed. The PTC is intact, looks clean and appears from the test to function correctly.

    I'm convinced that the PTC is going high-resistance before the compressor has fully started, but what's at fault? Have the properties of the PTC changed internally or is the compressor on it's last legs and finding it hard to get going in old age.

    I really don't wish to spend the equivalent of $70 on a start kit, to find out it is actually the compressor.

    Any suggestions?

56. Tim M on 2012-01-20 10:24:

    Sounds like it could be the overload protector, but it would pay to run the actual TESTS described here: fixitnow.com/wp/2005/12/01/refrigerator-warming-up-and-makes-an-occasional-clicking-noise/ It will also tell you how to test the compressor. Assume you have an volt-ohm meter?

    You have, haven't you, already unplugged the thing for 15 minutes, because you can't start the compressor when the freon is already compressed because it is too much of a load to start under?

    If you buy it here: pcappliancerepair.com/ It shouldn't cost anywhere near $70.

    If you buy it here: repairclinic.com/referral.asp?R=154&P=1 you can return it even if you install it, but it will cost more than the other place.

57. charles on 2012-01-21 08:22:

    Hi. i have a compressor that is off. when i switch on the power the compressor goes on/off in 2 seconds and repeat itself in a minute or so. i re-gassed it but the problem is still the same. tested windings and it gives me 94,92,124 ohms. what to do?

58. Mike7817 on 2012-02-08 14:48:

    I need help can somone explain what is going on... my refregerator start fine then get to freezing area ..then later it start not cooling enought we disconnect it 24 hours empty everything it works for 2 month or so then back again.... I found out if i run a small fan behind the refregrator that stop from happening for almost a year ..but it happen again.. disconnect it again 24 hours and it start fine again..iam not expert but what could be the problem the faulty part? and how to slove it ? thanks

59. Gajanan Gaikwad on 2012-02-29 03:43:

    Hi, I have Electrolux refreigerator with freezer. From last 3 days refregerator is not cooling..both sections freezer and refregerator...!! Light bulb in the refregerator is working...!! I could not able to here the compressors humming sound...How can I detect this fault. How can I check compressor? I did not found condensor fan in my fridge...!! Help me to find the solution... Regards Gajanan

60. Susie on 2012-04-19 13:55:

    A very informative and useful page that enabled us to get our fridge freezer up and running after the PTC expired. Thank you very much for sharing.

61. Dada oluwole on 2012-05-11 10:13:

    I'm a final year student of a university in West-Africa and i've being asked to work on solar refrigeration as my final year project. i've gotten the D.C compressor, but it has no starting relay. pls help me out because i don't know how to connect it with other parts without the relay. thanks

62. Admin on 2012-05-11 10:21:

    You didn't mention what your other parts are.

    I'm no expert, but it sounds to me like a DC compressor would not need a start relay - DC motors are high torque. Is there a label on the compressor specifying the input voltage? You may be able to wire it up directly to a power source and see if it runs. Naturally this is not expert advice - it probably should be run on a thermostat with other protective components in place - but you may already have them.

63. HarryT on 2012-06-01 16:11:

    Your blog post was very informative, but can I suggest adding one step to your diagnosis. After checking the 3 windings combination, you should also check each terminal to chasis. In my case, after the repair guy replaced the relay/overload he tried to plug the fridge back into the wall and it thew a large spark. After he left to check the price of a compressor, I decided to double check him. The ohm readings were in line with your suggestion, but one of the terminals was shorted to chasis.

64. Chilly Burr on 2012-06-20 19:45:

    I have a similar problem (except I have NO ice cream sandwiches...) with ultra-high quality Roper RT18BKXKQ00 a memorable model...

    I am so appreciative of you writing this hack for me to try tonight!!

    In my case, the Roper is the garage backup fridge that had a lot frozen-until-recently meat that turned into a cooking palooza then freezing a lot of new recipes in our main fridge.

    Have not ordered the part yet incase it's actually the compressor that said adios. At least I will know in several hours if I need to order that part or, go find a beautiful scratch & dent fridge for the garage.

    Thanks again for the humor and help!

65. Carl on 2012-06-20 22:52:

    Thanks for this informative article. This evening I discovered the compressor of our Maytag fridge was not running. The PTC had disintegrated and I was able to do the "momentary capacitor short" procedure you mentioned and got it restarted for now until I get a replacement part. In the mean time this saved the fridge full of food.

66. joe chasko on 2012-07-27 17:08:

    Very helpful - I had the same broken piece in the relay! Hooray! I admire your chutzpah in jamming the screwdriver in to test. I'll just get some dry ice if need be.

67. Mike on 2012-08-01 18:05:

    Very informative information here. I have taken the readings on the 3 terminals on my compressor (Magic Chef mini fridge) and come up the following readings (ohms): 8.5-11.5-18.0. Am I looking at a bad compressor? These tests were done due to the same problems reported here in these threads--fridge compressor not kicking in, clicking on and off, etc. Thanks for any help you offer.

68. Parsik on 2012-08-22 08:04:

    Thanks from Iran for this really useful site, all people are great posters, specially Bob and Andrew, I have learned a lot,. Anw way my 30 years old side by side Amana stopped working, I mean no cooling, fan works but the compressor refused to kick up, I tempered with the PTC and overload while the compressor was hot and I burned my hand in the process, so I took the relay out to let the condenser fan do the cooling of the motor, then I plug everything in its place and fridge started working great and happily for me and itself!

    so I have a question why the compreesor at the first place got overheated, could it be faulty thermostat or PTC or maybe compresser has passed its life expiedency?

69. trex66 on 2012-09-22 00:06:

    I have a mini fridge a friend gave me - not running. I can short out the wires to the PTC and get the compressor running. The high side tube tube is very, very hot but the low side is just ever so slightly cool. My question is, could low coolant have worked the compressor harder and burned out the PTC starter? I feel like i should recharge the fridge and get a new PTC?

70. Walter on 2012-10-08 17:08:

    Thanks for very nice post and discusion. I wonder if this post is still alive. I have a silly question. Yesterday my side by side refrigerator went bad. Both compartments are warm. I have checked that both fans are working. I have checked the compressor for continuity between connectors, there were no problem. I have checked compressor for ground, it was ok too. So now is my problem, after I have plugged refrigerator to outlet. I can hear two fans and the compressor is making spinning noise for about a minute. Then it is very quiet and make very small vibration. It never get hot or even warmer than room temperature. The two lines that comes and goes from compressor don't change the temperature even after few hours when both fans were working all the time. My guts feeling was that start overload unit was basted (there is no rattle sound when shaking the starter) but I am not sure anymore. Any ideas why compressor don't warm up over the time. Is it normal it this refrigerator model? What is the simple test if compressor is running? Any ideas what I could check before buying new starter/overload unit? Thanks for your help. Walter

71. Jim Nitzberg on 2013-03-28 22:35:

    Wow - Great pictures - matches the back of my fridge exactly. Now I have a question - how the heck did you get that plastic cover back on after you used those substitute parts??? Is there FIRE danger if you leave that cover off?

    Thanks again for the great pictures/great explanations.

    Sincerely, Jim Nitzberg

72. Rob in Bothell on 2013-04-10 10:35:

    Thanks! similar situation and your blog saved me a freezerful! Now I'm chillin again, waiting for the stores to open.

73. Jay J on 2013-05-01 09:53:

    Wow ...... thanks for posting this. Living in latin america, (or many places) one can not run to the parts store. Got the fridge running and now I can try to get the part and not a new fridge. The only thing you overlooked about running the fridge till it got cold is the automatic defrost timer that's running behind the scenes. If I need to run the refridgerator for a while using this manual start procedure, I'm going to bypass the defrost timer.

    One other thing ....; I decided to put some wire leads across the capacitor. I extended them and loosely tied them together. I plugged in the fridge, then pulled apart the wire leads. I taped the loose ends to prevent a short or shock. I did this so I wouldn't have to use the screwdriver method. There isn't a whole lot of room to do that in this unit without possibly touching something else with the blade.

    Again, super thanks to you !!!!!!

    In this country (Panama), they sell delay relays that plug into the outlet. They are for any devise that you don't want to immediately start after a power burp. Costs about $20USD

74. Jay J on 2013-05-01 10:57:

    Jim Nitzberg, I would tape the cover on. It holds the parts in place and keeps the live components insulated from you and the critters that crawl behind appliances.

75. Mo on 2013-06-11 14:04:

    Just a "Thank you". I never know who to trust in cyber world. Shorting across a capacitor to jumpstart the compressor with the bad relay, to see if it was worth taking a chance on a new relay. That was a scarry move for me, but all worked out well. And thanx for link to "Repair Clinic". One week to get the part, but the promised one year return policy "no questions asked" is unbeatable. My search results were that modern refrigs have 10 year design life. One repair dealer told me not to invest in my 11 yr old fridge. Just installed new relay, all is working perfectly so far. So only time will tell if the $51.50 and a one week delivery was worth it, but your help was precious. Thanx again, Mo

76. Max on 2013-06-19 18:55:

    Thanks for posting this!
    I found a big and very clean freezer on the street on trash day and the starter was Fubar. This page helped me manually start it and now i know its working all i need is to buy a new starter.

77. Ryan on 2013-08-16 02:37:

    Thanks for sharing your troubleshooting experience! I am a heating and air conditioning technician and I bought this stainless steel fridge for $50 cause it doesn't get cold. I noticed the compressor wasn't coming on so I was looking all over the fridge for a start capacitor and couldn't find one. I been wracking my brain over this for days! And I personally would never intentionally create a short in an electrical circut, but you had the balls to and it gave me some insight. THANKS!

78. Tony on 2014-01-31 16:24:

    I have read this blog with great interest and find some very good information here. I do want to respectfully disagree with the recommendation not to use a 3-n-1 kit.

    The information from Electrolux is referring to a situation where there is a real physical or electrical reason for hard starting. On this blog you’ve been talking about repairing the starting circuit on an otherwise “good” compressor, not a hard starting one. If you test the windings and find the ohm reading of two terminals pretty close to equal and one the sum of the two, and none of the pins shorted to ground, the chances are pretty good the compressor is fine.

    With that being said, the compressor could have internal parts wear that require it to pull more current to run than the normal rating…. We’ll call this a bad compressor. Some technicians know a compressor is bad and install a 3-n-1 kit to “force” them to run… this is a bad practice and could cause the issues referred to in the Electrolux bulletin. But even the factory starting components can and will fail under the extra load and cause a fire. I had a Maytag side-by-side do this at my sister’s house this year during Thanksgiving and it had all factory components. So the issue is not so much the 3-n-1 kit but rather the excessive current draw of a bad compressor or bad troubleshooting by the technician.

    We use the Supco RCO410 3 n’ 1 Start kit. It’s rated for ¼ - 1/3 H.P compressors and works beautifully on a good compressor. This Kit is a Solid State Relay, Overload Switch and Start Capacitor combo. It’s a simple install and it replaces all the components in the start circuit with new ones for only about $20 bucks.

    I started using the 3-n-1 on some cheesy “Chinese” small upright freezers that are impossible to find “factory” parts for. They have worked well for a very long time and I have many of them in service. I would not hesitate to recommend them as long as you do your homework first. Check the compressor as described above and you should be ok. I have dozens of the 3-n-1 kits running over 10 years or longer. You be the judge.

    And just so you guys know my background… I’m an IT/Network guy but I went to school for and made a living as an Air Conditioner and refrigeration repairman while going to school for Computers.

79. evan on 2014-02-20 01:38:

    Just found this blog after a search, and thanks to your reverse-engineering information, I was able to get my fridge's compressor running until the new PTC arrives. THANKS!

    BTW: my method was to wire a regular light switch across the capacitor's terminals. After the compressor starts, I can simply switch it off, then on again when it needs to start. I also had to attach the spades directly to the pins on the compressor since my PTC was totally fried.

80. Robert Hudson on 2014-07-09 20:00:

    I have a Maytag side by side freezer/fridge. If the electricity blips off for only a split second, the fridge compressor shuts down, and only the fan runs, and everything starts defrosting. If I unplug the unit for a couple of hours, something seems to reset and it will start immediately cooling again. What can I do to stop it from tripping out every time our electricity blips?

81. John July on 2014-07-12 16:59:

    They have time delay relays here in central america for that. But the time is only set for 3 minutes .... enough time for the system to depressurize and allow the compressor to start without the extra head pressure. Can yours restart after a 3 minute break?

82. Alberto on 2014-08-15 19:13:

    Hi, Admin. I have a a 15 year old GE Refrigerator B Series model #TFX22CRBBWW. I read your initial article, which is hilarious and VERY INFORMATIVE. My fridge had the same symptoms as yours. So, I pulled the PTC and the Overload (2 different pieces that fit together to plug in the 3 prong receptacle on the compressor) and the PTC rattled like a Brazilian maraca.. So, I went online to searspartsdirect.com compared pics with actual PTC/overload and decided they were the same. So I shelled $110 for both parts and overnite shipping. Today is Friday (problem was detected last night), Monday I get the parts. Keeping fingers crossed, but I think it will solve the problem... I will be back with the results.. Wish me luck. I am not shorting the capacitor to jump start the compressor. My life is worth more than the fridge..

83. Alberto on 2014-08-18 14:17:

    Well, I got the parts, plugged them in. And it worked for about 10 min (was cooling nicely), then stopped. Checked the connections,on the new parts, shook the PTC, no rattle. Juice is going in, but no cooling. Maybe the compressor is dead (readings 4,8 and 12). And gave up. Will buy a new refrigerator... Fixing might cost more than a new one in the long run.. Thank you, Admin.. Great job!

84. Alberto on 2014-08-18 17:42:

    Hey, it works again! It just shuts off every 10min (thermostat) and re-starts.. THANK YOU ADMIN. The PTC and the Overload are tricky to install: If you have a GE TFX22CRBBWW, plug the black wire on the Overload and plug the overload in the upper pin of the compressor (make sure the two "legs" point down). Then plug the orange wire on the PTC and plug the PTC on the two lower pins (paralell to each other) of the compressor). Make sure you have good contacts. The wires should not be loose.

85. John July on 2014-08-19 09:17:

    Robert Hudson, There are plug-in protectors you can buy. They sense under and over voltage and shut down the power to the plug. When the power is resumed, there is a 3-minute delay before the plug is re-energized. This prevents starting up against a load.

86. john menendez on 2014-10-01 09:24:

    john, (or anyone) can you tell me how to safely remove the PTC and overload from a DA73 compressor

87. Baba Para on 2014-08-26 19:14:

    Fridge and freezer stop working, but once I shake it hard starts to work Can someone help me?

88. MeSmart on 2015-01-21 12:56:

    Thanks for the blog post which gave me the knowledge (enough) to feel like I knew what I was doing. I am going to one up your post by saying that I took the rattling relay and with aknife and almost no effort , Opened the relay, took the two largest chunks of busted metal/compound whatever it is, and i wedged them back inbetween the obvious two sides in the center.

    Instantly my fridge went back to working as if nothign was wrong and I actually think i don't need my relay that is in the mail now.

    Hopefully it will cool everything down again .

    I accidently shorted the overload at first tryign to get to the relay area in this ancient renter home fridge. So i would suggest you update your post with this suggested route as there is a good chance the relays people will be attempting to short out with your method could easily be mcgyvered from the inside.

    If you have your old one you could maybe doo a picture version of what i suggested

89. Admin on 2015-01-21 15:24:

    Based on the comments, you are the 3rd person to use the chunks of the PTC to make do while you wait for the part. My guess would be that the pieces will not last long, but YMMV. Good luck!

90. BMWEGR on 2015-03-01 18:13:

    Thanks so much for putting this up for all of us, I was able to do the same "jump stating" of the compressor until I figured out a permanent solution. In my case I was able to use a new ptc/oc device to eliminate the capacitor. I bet half the fridges left by street side could be fixed with $50 in parts.

91. KenB on 2015-10-13 06:48:

    Thanks for the great diagram and explanation. Much appreciated.

92. Magyver on 2015-12-13 09:57:

    Hello my friend. It seems you have a quite successful repair thread going here that has helped many people, including me. My ammonia RV fridge died and my mini fridge was dead, so I have been tinkering on my mini fridge - turns out the thermostat contacts were fried.

    So far I can't find a cheap generic thermostat on line, so I guess I'll try to pull a used one out of a junk unit. Holler if you have a link for a cheap generic thermostat!

    Next step is to go to the local Goodwill store, and tell the guys in back that I'll give $5 for any used mini fridge they get that won't run.

    Odds are many will run with a $10 3-in-one from Amazon for a 1/12 to 1/5th HP motor. I may just try to pick up a couple of dead chest freezers and try my luck.

    Thanks again Akom, I'm a Yank from Mississippi, and have a few sports blogs myself. Leave me a message, I'll be checking back.

93. Admin on 2015-12-13 11:21:

    If your RV fridge is anything like mine, the only moving part is the propane solenoid, so I'm not sure what you're planning to do with a 3-in-1. The plan to extract a thermostat from a dead fridge seems sound, but depending on the thermostat type you may need to add a relay to reduce the current load. May be easier to buy the proper OEM replacement thermostat from the manufacturer.

94. Christy on 2017-05-11 04:25:

    My freezer or fridge won't cool right. Temperature is too high for fridge, 70 and freezer 58. The compressor keeps running off and on a minute. It only stays on for 30 seconds. have used a multimeter to check cooling and wiring in the front of the fridge, which everything seems to be working ok, but haven't checked the back yet. My thoughts it may be the start relay or the compressor. Can you tell me what may be wrong, anyone?

95. domore on 2017-06-30 20:22:

    Very helpful information. My Kirkland/Whirlpool had no wiring schematic included and this site and a 6A momentary switch from the shop got the fridge back up and running for three days while I waited on parts. Make sure that you use a timer to interrupt the power supply after an hour of runtime or so. The fridge will try to start back up without the relay and really heat up the compressor. BTW, nice response to AZZY re: having to know it all before utilizing it. By now AZZY has given up on breathing since he couldn't figure it all out beforehand. Thanks for putting this out there.

96. Ricky P. on 2017-10-09 13:08:

    Tim M., You are spot on. And Akom, you are a genius! Can't believe you went into such elaborate detail, exploring, locating and then explaining a problem (and solution) in an area which you previously had no expertise in. Truly impressive. You should be a teacher.

97. Mark R on 2018-01-03 17:39:

    Thanks for the clear and helpful information here. My fridge broke down on Christmas Eve, full of food and with no repair shops open. Your info helped me to verify that my PTC and compressor seemed OK, and gave me the confidence to test them directly. I narrowed down the fault to the control PCB, probably a capacitor or varistor. Instead of replacing the board I've built my own IoT Raspberry Pi controller, taking care of the compressor, the light and the evaporator fan and posting results online. I'm planning to expand this to include alarms for temperature and 'door left open'.

    If it wasn't for your page I'd quite possibly have scrapped the fridge and be looking for a €1,000 replacement today. Thank you so much!

98. Admin on 2018-01-03 20:09:

    That is awesome! I'll keep that in mind if I ever face this issue.

    Random ideas: tracking and analyzing usage, predictive cooling, temperature-sensor controlled evaporator fan (rather than always on). You might be doing some of this already.

    I never would have guessed that my blog entry would become this visible, but I'm glad it helped.

99. roger shingleton on 2018-02-18 16:47:

    220V Electromagnetic Compressor PTC Starter Relay 1/3 HP Refrigerator Part... They sell two of these. One is a 1/3 hp and one is a 1/6 hp/ Any way I can tell which one I need before I order.....Magic Chef refrig. # RB17E *-1A Number on relay is Z204 MM5-74S... Thanks for any help....

100. Hebekiah on 2018-02-23 00:52:

     Roger, if I had to guess, going for the larger capacity one can't hurt much as it will either just be tougher or merely run both windings for a moment longer.

101. Hebekiah on 2018-02-23 01:01:

     To add to this for large freezers or AC heat pumps that basically do the same thing, another similar situation is the fan not starting; it has a relay and capacitor too. Usually a push with a stick is all that's needed to get the fan moving. I've actually replaced more capacitors than relays on them and that's good because the capacitors are only $8-12 for the big ones.

     If I were replacing that relay I'd maybe go ahead and replace the capacitor as well. For a regular fridge or freezer it's probably $5-10

102. Charles E on 2018-03-15 16:14:

     My frig quit after a power brownout. It has a 3in1 installed, not a Hard Start. Disconnecting the wires from the capacitor.I get 120 V to both windings, but no start. The compressor Ohm readings look normal. Could it be a mechanically seized compressor that needs to be replaced, or is there something else I should look at?

103. Karim on 2018-05-31 07:25:

     Help please!

     Firstly, I would like to apologies for my lack of anything-electrical related knowledge.

     Moving on to the problem at hand.

     The Fridge (standalone Hotpoint RLS150G - 9 years old), suddenly stopped cooling. There was no noise coming from the fridge, thus a tiny bit of research made me assume that the Starter Relay (PTC - thingy) was shot. I took it off the compressor, and tested the compressor using a multimeter, The compressor seems to be working fine, with the readings checking out at 8ohm, 5ohm, 3ohm. The Starter Relay (apologies if this it not the right name) doesn't have any broken parts (as it doesn't rattle), but it does have some slight burn marks, thus I assumed it would be best to replace. I could not find a replacement part on espares.com for the fridge in question, however I did find one that looked EXACTLY the same, and thus purchased it. Unfortunately, it does seem to have solved the problem, and the compressor still does not want to start.

     Doubly unfortunately, the wirings of my fridge look nothing like that you have kindly drawn above. All the wires (from the fridge and from the 3-pin plug) connect directly to the Start Relay.

     Any idea, how I can try and solve this, without forking out £180 for a repair company to simply come and fix it after 3 mins of labour.

104. KEN TRAN on 2018-07-08 22:04:

     I WAS ABLE TO GET THE COMPRESSOR OF MY MAYTAG RUNNING TO SAVE THE FRESH FOOD WHILE WAITING FOR THE RELAY PART TO ARRIVE LATER. I USED A SEPERATED AC POWER CABLE CONNECT THE BLACK ONE TO THE RUN WINDING AND WHITE ONE TO THE COMMNON WITCH IS AT THE CENTER THEN POWER AC ON AND USED THE SCREW DRIVER TO SHORT BETWEEN THE RUN AND THE START WINIDNG FOR A ABOUT THREE SECOND. THE COMPRESSOR RUN AND NOTICE THAT THE FREEZE IS COLD AND MAKE ICE. RUN IT FOR ABOUT 5 HOURS THEN TURN OFF OFR ONE HOUR AND RUN AGAIN. SOMMTIMES YOU NEED TO RUN COMPRESSOR TEMPORARILY TO SAVE THE FRESH FOOD. OHM OUT THE COMRESSOR MAKE SURE IT NOT SHORTED BEFORE RUNNING THE COMPRESSOR MANUALLY.

105. gabriel on 2018-07-17 16:14:

     Thanks to this site and others I successfully replace the start relay to fix my compressor not starting issue. That worked for a few days and then it stopped again. I actually swapped back in the old PTC and it started working again! A few days later it failed and i swapped back in the new one. After reading this post I realised one issue I was not waiting long enough between re-trying the fridge. however I am want to understand what it is that keeps tripping the PTC. I am assuming heat, since it has been very hot here in LA last few weeks (over 100F), but this has only just become an issue in the last few months. We have a home warranty that will charge $75 to send out someone and fix whatever the issue is, including replacing the compressor. Do people think that this constant tripping of the PTC when hot is a symptom of a dying compressor. It's an expensive fridge ($2500) and good quality Jen Air so would rather not replace it unless I have to. How can I convince a repair guy that the job is simpler than just switching out the PTC?

106. Serge on 2019-07-08 11:04:

     Compressor running but not cooling . condenser coil inlet and outlet cold

107. Colin Q Bang on 2019-07-09 19:27:

     I bought a "start device" (relay/overload in your diagram) for my Kenmore fridge, to replace the faulty one. The one I bought is the original manufacturer's official substitute part according to searspartsdirect.com and other sources*, but it is not entirely plug compatible -- the compressor (3 pins) plug in fine, and the capacitor will fit onto the opposite side of the replacement device, but there is a pair of wires plugged into the original that can't plug into the intended replacement -- tab A doesn't match with slot A, basically.

     I can get the wires connected without the "plug", which is just a plastic shroud around a quick disconnect (ordinary "blade and sheath" connection, i don't know what else it's called) for each wire. But since the receptacle on the replacement doesn't fit the plug, I don't know which wire goes to which "blade" terminal on this replacement device. And the terminals aren't labeled on the replacement device. Ironically, the original device does label them -- "N" and "L", respectively.

     1 wire is red, 1 is blue, coming from I don't know where. I think this is just the power supply, unless that is coming into the compressor from somewhere I didn't see. If it is just supplying Alternating Current power then it wouldn't matter which was on which terminal, right? In which case, the terminals wouldn't need to be labeled, but on the original device they are, so that makes me think maybe they aren't the AC power. I guess I could use my multimeter on it while it is plugged in, though I don't think that is considered very good or safe practice.

     :q!

108. AdamP on 2022-01-23 22:11:

     Thank you for the write up, and thank you to RonK for sharing the idea about opening up the busted start relay and using the two biggest pieces as a temporary fix while waiting for the replacement. So far the temporary fix is working perfectly!

109. Rick on 2023-10-01 22:51:

     Hi, I (an electrical engineer) wanted to point out that you CAN NOT charge a capacitor with 110AC, or any AC for that matter. You have to use DC.

     You might be able to use a 9V battery. (I haven’t actually tried this to verify).

     Put your multimeter on Volts. Connect it to the capacitor pins (either way, it doesn’t matter). The meter should read 0V (or very close to it) at this point.

     Touch the 9V battery to the pins (again, either way, it doesn’t matter).

     With the battery connected, the voltage should very quickly go to 9V (or -9V). Disconnect the battery, and it should decay kind of slowly back to zero (how quickly will depend on your meter).

110. Admin on 2023-10-02 09:19:

     Thanks for that, Rick, that makes sense.

     It may also be worth pointing out that nowadays most digital multimeters have a capacitor test function.