GE refrigerator is not cooling

[tony tan]

Hi,

My GE refrigerator  (PFCS1RKZH SS)is not cooling. both fans are running. compressor is running for a long time because the freeze side is always 33F.  Fridge side is room temperature. I found some ice built up on evaporator coil, but not too much. I jumped J9 and J11 to direct let 110V ac to bypass relay to let heater on. the heater is very hot. so the heater and thermostat is OK. I have changed the new invertor board and main board. the compressor has noise and I can feel vibration. I check there is 110Vac to invertor board and there is 5vDC from main board to invertor board.

 

what will be the problem? thermistor or leaked Freon??

 

please help.

[16345Ed]

A photo of evaporator frost pattern would be helpful 

 

if you have infrared temperature gun shoot a temperature of the condenser coils and get an ambient room temperature reading as well and report back. 

 

Could be thermistor issue. But let’s try to rule out sealed system issue first. 

[LearningTech]

It has a leak  or restriction in the sealed system, or weak compresor. 

 For futrure reverence. If the compressor runs, and you do not get a conplete frost pattern. Then you have a sealed system problem.( with exception of you may have extreamly  dirty coils.  

 If the compressor runs. Then stop you r diagnoiss unless  you are already willing to put 600 plus into the unit.  So  unless that is the case it does not matter what exactly is  the issue as you  will likely just buy a new fridge rather than put 600-1500 into unit.

Never replace a board ( for no cool) if the compressor runs.

and never replace a inverter  if compressor runs.

[16345Ed]

58 minutes ago, LearningTech said:

For futrure reverence. If the compressor runs, and you do not get a conplete frost pattern. Then you have a sealed system problem.( with exception of you may have extreamly  dirty coils.  

For future reference...

No need to view frost pattern if condenser temperature is not 30 plus ambient temperature. Saves a lot of removing items and tearing into unit. 

[J5*]

3 minutes ago, 16345Ed said:

No need to view frost pattern if condenser temperature is not 30 plus ambient temperature. Saves a lot of removing items and tearing into unit. 

That’s all good for a unit that has a visible condensor

checking the evap is a good idea of what’s happening 

[mxzx]

I have a similar problem, fridge model PSC23PSWCSS (10 years old)

I saw an uneven frost pattern on the freezer side evaporator.  Frost / ice on the bottom 6 inches.  Compressor is running constantly.  But my compressor has three speeds.  If it was stuck on low or medium, is there a chance it might not get to the temperature setpoint and cause these ice / frost patterns? 

My last ditch idea is that the main board is sending the inverter a bad signal but not sure i want to spend another 250 to try (I already tried replacing the inverter).

(or bad compressor, refrigerant leak (although no oil stains found anywhere), sealed system blockage, 3 way valve problem) 

Some other facts:

Freezer is at 27 deg F, set to 0 deg F.  Fridge is at 52 deg F, set to 37 deg F.

All fans working, condenser is clean.

Condenser temp is approx 78 deg F and ambient is 71 deg F (by infrared heat gun)

Compressor body temp is 100 deg F

Compressor windings are 7.4 to 7.6 ohms and no short to ground, all three combinations are similar (GE service manual says they should be 9 or 10 i think).  

Inverter is getting 120V and 5 VDC (about 70 Hz).   Service manual says on fridge startup compressor will run at medium speed, and then jump to high speed once freezer is within 20 deg F of setpoint.  Once it got to 18 deg F from setpoint, the 70 Hz from the main board to inverter did not change.

I did try changing the inverter.  Old inverter was sending ~120 VAC to the compressor.  New inverter was sending ~ 170 VAC.  I thought this would be the fix, but i was wrong.

I looked at the 5 VDC signal on an oscilloscope, thinking i would see a nice square wave.  It was messy.

Any ideas?  

 

[16345Ed]

19 minutes ago, mxzx said:

I saw an uneven frost pattern on the freezer side evaporator.  Frost / ice on the bottom 6 inches.

Sealed system issue, no electronic issue. 

 

20 minutes ago, mxzx said:

Condenser temp is approx 78 deg F and ambient is 71 deg F (by infrared heat gun)

Another confirmation of sealed system issue 

[LearningTech]

1 hour ago, 16345Ed said:

Sealed system issue, no electronic issue. 

 

 Unless its an elecroninc sealed system issue, such as a stuck 3 way valve can act like restriction.

could be electronics doing it. Or could be mechanical

Edited July 18, 2018 by LearningTech

[16345Ed]

43 minutes ago, LearningTech said:

 Unless its an elecroninc sealed system issue, such as a stuck 3 way valve can act like restriction.

could be electronics doing it. Or could be mechanical

Great point! Yep could be  the valve didn’t even check to see if this one had one. 

 

[mxzx]

Yes it has a 3 way valve.  One check i read about for that was when plugging in the fridge feel the valve to see if it does something.  I tried this and it does do something when plugging in the fridge.  I don't know if it is doing the right thing though, all i know is it isn't dead.  I've thrown in the towel and I'm buying a new fridge.

Anybody want a PSC23PSWCSS for parts?

On a serious note, is there such thing as appliance scrap yards where I might be able to get a few bucks for it?  Or throw a few components on ebay...

[LearningTech]

13 hours ago, mxzx said:

appliance scrap yards

Just some random local shop. Usually ont pay more than. 10 bucks cause they get plenty free, ebay is better route to make more $ IMO