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nortonian

SubZero 550, Frig, Not cooling, Freezer Fine

22 posts in this topic

Hello there, I have a 550, March 92, Serial Number: P962848...

The frig is cooling intermittently , it varies between 50 degrees to 39 degrees, with no identifiable pattern. The two switches were replaced today, the switch which is the power for the lights was bad, and the other switch right next to that one was also replaced... the guy that replaced them stated that the switches were bad and replacing them would fix the situation... We are four hours from switch replacement, no change in cooling...

Here is what I know: It is noisy, the fan seems to be running constantly., A week ago the grill above was so hot you couldn't hold your hand on it for any longer than about 5 secs...the grill is now cool, and I have no idea why the change. (all clean behind the grill)

The temp is occasionally very cool, but pretty regularly it is hovering at 50. The "repair guy" (he is very nice and a layman, who has alot of experience with other frigs) didn't think it was the evaporator (although I don't know how he would determine this as he did not remove the back panel...) he listened with a stethoscope to the compressor and said he could hear the freon, thus it couldn't be the evaporator...this does not seem to be the method of diagnosis for evaporators in these forums...

Obviously obviously, this is a challenge to diagnosis with such little information, but I wondered if someone has the time if they could possibly tell me what to check/troubleshoot ...

In advance I do really appreciate any time you may have to assist...

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Need appliance parts? Call 877-803-7957 now!

You, intrepid Nortonian, have answered your own question...

Remove the shelves and the back wall and feast yer peepers on the famous evaporator coil...

Post us a shot so we can enjoy it with ya...

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What fan is noisey? Why was fan switch replaced? When door is opened and switches depressed dose light go out and fan come on?

Was there any frost on back wall of ref? Need to check coil and pressures.

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Thank you both so much for taking time for answer... when switch is depressed the light goes off. The fan doesnt change. I have not pulled off the back wall, and I don't want to (if I say that loudly and stomp my feet will that help at all?) yeah, didn't think so...

Ok will play rock paper scissors with my husband for who removes the panel, then will take pictures and let you know what I discover... thank you.

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Sounds to me like possibly a bad condenser fan motor, the one up on top that cools the condenser and compressors maybe intermittently not running, (the hot panel that you can't hold your hand on because it's so hot leads me in that direction).

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Hi everyone, sorry for the delay in getting back, our Kombi-Core system decided to go down right after this post... so, first thanks for the posts, I became an apprentice and appreciate the ability to contribute to this forum as I have learned ALOT...

Ok, so the evaporator looks lovely, no ice, no frost nothing at all, no corrosion, still looks like galvanized metal off the factory floor, BUT exciting news the Refrigerator Evaporator Fan Motor was NOT running, at all.... (Yes we pressed the switches so the door triggered closed, no go).... we are picking up the part, will replace and see if the frig finds happiness and my veggies stop freezing and my meat stays cold...

I did miss the flow chart when I first posted and do feel bad to have not seen it as its extremely logical... so, finger crossed the issue will be resolved...Thanks again, will update if its not a fix...

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False alarm. The fan for reasons we don't understand has started to work again. ? ? ? No idea what that means or how it started spontaneously... what it just stuck and when we cleaned off the dust we "unstuck it", or perhaps it just has a dodgy motor which means its intermittent? Darn, thinking it was an easy solution... going to watch the temp for a couple hours see if the fan is the key anyway... hmmm .

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Now I am just being annoying.... fan is in fact intermittent. Its off again, I am not feeling so crazy.... back to replacing fan.

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Is ref compressor running when ref fan is off? Need to check for 110v at motor when it is not running. May be cycling off with cold control. If evap is good and unit is cycling off while warm cold control is bad.

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Hello... so no the fan did not fix the issue, but it did create a new piece of information:the fan is still intermittent... so last night the fan was humming along the frig was getting tooooo cold, I turned the frig down to 5, (did not check fan was working by depressing switch as I didn't think about it) woke up to a very warm frig and the fan not running again... I dialed the temp to 7, fan clicked on... just checked it played with the dial, took it to 5, fan was running no problem back to 7 fan stopped running... doesn't seem to be the temp gauge, leaves me thinking the switch is bad, or there is an issue in one of the electrics... however see below:

Is ref compressor running when ref fan is off? Need to check for 110v at motor when it is not running. May be cycling off with cold control. If evap is good and unit is cycling off while warm cold control is bad.

In reply to this post: the compressor IS running Constantly... regardless of fan off or on... it ran when the fan was disconnected during the replacement...

Sounds to me like possibly a bad condenser fan motor, the one up on top that cools the condenser and compressors maybe intermittently not running, (the hot panel that you can't hold your hand on because it's so hot leads me in that direction).

In regards to this post: I found the schematic for the 500 series, and I found the condenser fan motor, nicely highlighted in a little circle, but I did NOT find where that little circle was located on the frig itself... there is no line returning from the condenser fan motor back to its actual location...... all that being said, I do not know from that schematic what I do to check if the condenser fan motor is bad...cause I can't find it...I am sure its very easy to check, but could use a little nudge in the correct direction...

Thanks for any ideas....

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The Condenser Fan is above, behind the Grille that cools the Condenser Coils and both Compressors.

It runs continuously on that model / serial number.

The newer series uses a Relay that only runs the Condenser Fan when either Compressor is running.

The Evaporator Fan inside the Fridge runs anytime the Fridge Compressor is running

(if the Fridge Door is closed)

pagefromsubzero500serie.jpg

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Sounds like the cold control is the culprit. How are you determining that the compressor is running constantly?

this puppy has 2 compressors so you can't go by sound...

if you haven't been able to see where the condenser fan is, I assume you haven't opened the machine compartment.

open her up and put your hand on the small comp. May be pretty hot...feel for the vibration to tell if it is running.

do this when you find the fridge warm ,when it should be running.

While yer up there, as Willie said, make sure if either compressor is running, that the fan up there is running strong.

Also be advised, a clear evaporator, no ice no frost no water, is not a good thing...Ideally, you should have an even light coating of frost over the whole coil after the comp. Has been running 20-30min...

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Ok, thanks, just needed to open it up, it was all so clear at that point.... Fan is running very STRONG, no issues apparent.....Small compressor NOT RUNNING when frig is warm... (opened frig door let it get warmish), no vibration, it was warmish to touch... large compressor hot and running....

and back to evaporator for a second looked at it again last night, flashlight on it and in fact light sheen of frost all over, sorry about the misinformation earlier...

Is that the cold control? Or is that the compressor being bad?

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Need to graduate to live voltage checks to make absolutely sure...remove the electrical cover from the fridge compressor and test for 120vac when it should be running.

If you have voltage, bad relay or compressor. No voltage, cold control.

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... Small compressor NOT RUNNING when frig is warm...

... Is that the cold control? Or is that the compressor being bad?

Was the Fridge Evaporator Fan running at that time ? (Fridge Door Switch closed) = YES = Compressor problem

NO = bad Cold Control

 

41B7%2BR-ar7L._SL500_AA300_.jpg

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Ok, need a little help, here is a picture of the small compressor and what looks to be the electrical cover with a LONG silver nut holding on the cover, the nut has threads on the inside, and is a standard hex nut on the outside, do I need a special tool to take this off, OR am I over thinking it and I just need to unscrew it... I will try to figure out how to get a picture into this post next, have picture but maybe you don't need it to answer? Thanks...

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Was the Fridge Evaporator Fan running at that time ? (Fridge Door Switch closed) = YES = Compressor problem

NO = bad Cold Control

Ok have not checked for voltage yet... here it is: frig warm. evaporator fan NOT running, small compressor Not running... sounds like Cold Control it is!! I assume the cold control will come with installation instructions, do I need a frig tech with specialized tools to replace it? My husband is a tool maker, so if its simply taking apart and putting back together, then I don't think that is above my pay grade with a little assistance... :)

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Naw, it is a direct replacement for what's there now...2 wires ,2 cap tubes and done.

Be careful crimping those caps in the coil...sharp edges!

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Fantastic, thank you for all the feedback and super fast responses... will order part and see where we are mid week.... Have a fab weekend!

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Ok, good news!! Cold control was installed. Its was sooo easy!! And its been about 24 hours, and so far, the cold is steady!! Very very pleased!! Thank you so much for walking me right through the diagnosis and the repair...you all were so helpful and explained things so logically... soo I am starting to believe this frig is going to be ok...

One last question: as this is an older model, and the condenser fan runs constantly, can a relay be installed in this model?

Sooo thank you thank you! This was frustrating, but it was also fun to learn !!

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you would need a 120v AC dual-coil Relay and connect it as shown

looking at wiring diagram:
One Relay Coil #4 (bottom, left) connects to Freezer Compressor
Other Relay Coil #5 (bottom, center) connects to Fridge Compressor
Common terminal of Relay Coil #6 (bottom, right) connects to Neutral
Fan (Line power) is "split" and Relay Contacts inserted
One Relay Contact #1 (top, left) connects to Line power
Other Relay Contact #3 (top, right) connects to Fan

subzero500fanrelay.jpg

http://www.repairclinic.com/referral.asp?R=154&N=1567820

 

Compressor-Sealed-System-7014395-0068915

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Nice work, norton! That makes me feel like a dancin' fool!

5a.gif5a.gif5a.gif

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