Kitchen Aid Refrigerator KRMF606ESS00 - Fridge not cooling

[OmarE34]

Hi folks,

I'm new to this community so please bare with me. I'm having a classis fridge not cooling/freezer cooling OK issue happening on my Kitchen Aid refrigerator. Below is some more info i've gathered to provide some insight to the issue. But long story short, I've had this fridge for about 5 years now and its been nothing but headaches and service calls. My situation now is that if I can troubleshoot and repair this thing on my own (i'm not technical in fridges) than I'll go ahead and plan to keep it, and if not than I don't think I'm going to shell out another $500-$700 for a tech to come out so i'll probably pull the trigger on a new one. 

-Compressor seems to kick on and work OK 

-Freezer works OK/ Fridge is not cooling at operating temp 

-Defrost heater seems to work OK? I disassembled the back wall of the freezer and saw it running through the defrost cycle. 

-Freezer fan kicks on OK 

-I was told by my Dad that the last time it had this issue, he unplugged it and let it "defrost" for a day or two and then turned it back on. After turning it on, it worked for about a week then had the same issue. My thinking is that the issue may be somewhere in the defrost cycle, if not on the coils then possibly some kind of frost build up that is not easily viewable, possibly the airway to the fridge? At any rate, my thinking was to begin replacing the thermistor and bi-metal piece and see what happens. I've attached pictures of what I think those two pieces are. 

Side note- I did manage to run a few diagnostics test on the fridge but they mostly came back inconclusive. Service Test 6- Defrost Heater/Bi Metal did return an "03" which was odd since the guide only gives two possibly results- 01= bi-metal closed or 02=bi-metal open. 

Pics of the temp and what I think is bi-metal sensor: https://syedumarahmad.imgbb.com/

 

Sorry for the long post. Any help is greatly appreciated!! 

Omar 

[Vance R]

This is a dual evaporator refrigerator. Look at the evaporator in the fresh food section for ice buildup. It is located behind the crisper and deli drawers. If it has ice build up on outside the evaporator will need to be manually defrosted. Your pictures are of the freezer evaporator and thermistor. 

[OmarE34]

5 hours ago, Vance R said:

This is a dual evaporator refrigerator. Look at the evaporator in the fresh food section for ice buildup. It is located behind the crisper and deli drawers. If it has ice build up on outside the evaporator will need to be manually defrosted. Your pictures are of the freezer evaporator and thermistor. 

Thanks for the reply, Vance. 
 

In fact, after defrosting the fridge for 24 hours I noticed a pool of water underneath both fresh food sections. So I think that would explain what may be blocking or preventing cool air from entering the fridge. 
 

Do you know why this build up may occur or what I should look into diagnosing? I’m afraid after turning it back on it’ll work for another few days then I’ll run into the same issue. 

[Vance R]

For the fresh food evaporator whirlpool doesn't use a heater to defrost. The refrigerant flow is turned off and the fan is left on to melt the ice.  Need to remove the evap orator cover to complete remove the ice build up. Use of steamer is the best way to melt all of  the ice. If you do it by turning off the refrigerator the door would have to be left open for 2 to 3 days and place towels aroubd to refr ig to soak up the over flow from the defrost pan. Steamer is the quickest way but will still take a couple of hours. The thermistor will need to be replaced and move to the suction line. Make sure the clip is tight and zip tie the thermistor in place. The defrost pan must be flat and the evaporator should be moved back to touch the back wall. Whirlpool recmends use of zip ties to hold evaporator in place. Reinstall the cover with all 4 screws and make sure it seals to the liner.  Last is to get into daig mode and change defrost from adaptive to maunal.

[OmarE34]

49 minutes ago, Vance R said:

For the fresh food evaporator whirlpool doesn't use a heater to defrost. The refrigerant flow is turned off and the fan is left on to melt the ice.  Need to remove the evap orator cover to complete remove the ice build up. Use of steamer is the best way to melt all of  the ice. If you do it by turning off the refrigerator the door would have to be left open for 2 to 3 days and place towels aroubd to refr ig to soak up the over flow from the defrost pan. Steamer is the quickest way but will still take a couple of hours. The thermistor will need to be replaced and move to the suction line. Make sure the clip is tight and zip tie the thermistor in place. The defrost pan must be flat and the evaporator should be moved back to touch the back wall. Whirlpool recmends use of zip ties to hold evaporator in place. Reinstall the cover with all 4 screws and make sure it seals to the liner.  Last is to get into daig mode and change defrost from adaptive to maunal.

I was able to take apart the evaporator cover and get access to the unit. Its all defrosted at the moment if you see the two photos here: https://syedumarahmad.imgbb.com

Are you able to indicate which line is the thermistor? It seems like its the first one right in the front although I noticed there is a bag type thing around the line and some gray clay material? I'm not sure what that might be. 

[Vance R]

From your second picture the black wires in the back going to the evaporator tube. The ends of the wire should have a metallic or white small cylinder.  In your first post of the pictuer freezer evaporator - the black wires with white cyclinder is what the thermistor looks like.  The thermistor for the fresh food evaporator is part of that wire harness in your second picture. That will need to be replaced and moved up the the braze joint on the suction line ( larger tubing) and zip tied in place.

 

The clay substance is a sound damping mastic to quite refrigerant noise.

[OmarE34]

33 minutes ago, Vance R said:

From your second picture the black wires in the back going to the evaporator tube. The ends of the wire should have a metallic or white small cylinder.  In your first post of the pictuer freezer evaporator - the black wires with white cyclinder is what the thermistor looks like.  The thermistor for the fresh food evaporator is part of that wire harness in your second picture. That will need to be replaced and moved up the the braze joint on the suction line ( larger tubing) and zip tied in place.

 

The clay substance is a sound damping mastic to quite refrigerant noise.

Got it, thanks for the explanation. Will go ahead and get this piece replaced and report back.

Thanks again for the help/knowledge share. 

[OmarE34]

On 10/7/2020 at 8:59 PM, OmarE34 said:

Got it, thanks for the explanation. Will go ahead and get this piece replaced and report back.

Thanks again for the help/knowledge share. 

Hi Vance/all,

Wanted to bump this thread again as unfortunately the same issue has sprung up again. I was lucky enough to actually find a Technical Service Bulletin direct from KitchenAid on the issue and their guidance was to simply relocate the thermistor and fasten (can email PDF on request, not sure how to upload it). 

I went ahead and did the recommended fix but two weeks later I found the fridge to start running warm again. Opened up the casing and come to find out the ENTIRE unit was covered in frost, literally all over including the bi-metal thermistor. I also noticed that it had changed color from the gold/copper color to a black shade. My guess would be at this point the sensor itself is shot but I'm at a loss in terms of troubleshooting further. My first step would be to find a new thermistor to replace, but was hoping there may be other suggestions. 

Pictures of unit and thermistor: https://syedumarahmad.imgbb.com/

 Again, any help is much appreciated! 

Umar Ahmad 

[Kirk0717]

Did you ever get your Refrigerator fixed?

[Nathaniel Peterson]

On 8/17/2024 at 9:46 PM, Kirk0717 said:

Did you ever get your Refrigerator fixed?

You have to splice in a new thermistor and use waterproof silicone on the blue wire nuts. If the white  foam on the e evaporator cover is water logged aka holding water that'll need replaced too. Make sure the drain isn't clogged before you put everything back together. If cover needs replacement check pictures of part number because some of these come with fan and thermistor already included if it's the cover that's attached to the fan and insulation foam. Fun job

[v8power]

On 8/24/2024 at 4:59 PM, Nathaniel Peterson said:

If the white  foam on the e evaporator cover is water logged aka holding water that'll need replaced too.

Would new foam get waterlogged through the same mechanisms that caused the original foam to get waterlogged?

[Nathaniel Peterson]

9 hours ago, v8power said:

Would new foam get waterlogged through the same mechanisms that caused the original foam to get waterlogged?

Yes,it's a design issue. Have a customer we replace every three years so far 

[v8power]

13 hours ago, Nathaniel Peterson said:

Yes,it's a design issue. Have a customer we replace every three years so far 

What symptoms does having waterlogged styrofoam cause?

Can waterlogged foam keep the coil too cold and the board thinks it needs to run the fan longer to "defrost" it?

I'm not seeing much water drip from the drain pipe.  The foam keeping water in the unit would help explain this.  I'm wondering if this is also a cause of my higher humidity levels.

[Nathaniel Peterson]

30 minutes ago, v8power said:

What symptoms does having waterlogged styrofoam cause?

Can waterlogged foam keep the coil too cold and the board thinks it needs to run the fan longer to "defrost" it?

I'm not seeing much water drip from the drain pipe.  The foam keeping water in the unit would help explain this.  I'm wondering if this is also a cause of my higher humidity levels.

Water logged foam will cause the coil to ice up and depending on how much of and where the foam is waterlogged depends on how quick it blocks air flow through the coil. If it were my fridge and I wanted to spend the money I would get the thermistor and the foam cover depending on if it's water logged W11188493 evaporator cover (white)W11087438 evaporator fan with thermistor and fan support. If you want to do it a little cheaper you can substitute the fan assembly and fan support for a thermistor but you have to splice in a new one and put waterproof silicone on the wire nuts or bell connectors so water doesn't get in. Don't remember the part number but I would get the Whirlpool thermistor part number that ends in 670 that's the brass colored thermistor. Not a cheap fix unless you're doing it yourself. You can always test the parts before you buy them. There's a thermistor chart on the Internet from this site but they usually go bad as they get colder. Should check by a small cup of water in a ice bath which would bring the water temperature to 32 degrees Fahrenheit.good luck

[v8power]

On 8/31/2024 at 11:30 AM, Nathaniel Peterson said:

Water logged foam will cause the coil to ice up and depending on how much of and where the foam is waterlogged depends on how quick it blocks air flow through the coil.

Thank you!

I confirmed some drops of ice on the coil where there was a waterlogged piece of foam (Support Bracket W11028224) right after a cooling cycle.  This was after replacing the evap thermistor a week ago.  I'll have to address the foam.

Separately, I found that the RC drain pan (W11720794) underneath the RC evap can hold water instead of directing it toward the drain.  This may be the culprit of my high humidity levels.  It appears the right side needs to be elevated more than just lying on the cabinet.  Is there a trick to installing it?