KitchenAid KRMF706ESS01 occasionally stops cooling

user21

Premium Member
Joined
Sep 11, 2019
Messages
8
Location
MA
Model Number
KRMF706ESS01
Brand
KitchenAid
Age
1-5 years
We have a 2 year old KitchenAid KRMF706ESS01.

Every few of days the fridge will stop cooling. After unplugging it, it will recover and seem to be humming along.

Below are the symptoms after it fails:

Cycles through this sequence:
1. Refrigerator valve clicks every second for a couple of minutes and stops
2. 2 seconds of rapid clicks and stops
3. Control board relay clicks and sometimes turns on the fan by the compressor for a about a second
4. Starts over

Other symptoms:

Compressor not running
Compressor fan not running
Light inside fridge do not turn on
Light on front panel working
Panel otherwise responsive
Water is not dispensing

I would really appreciate any help diagnosing the problem!

Thanks!
 

rickgburton

Appliance Tech - Moderator
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On the power supply board check for a constant 120 VAC P1-1 to P1-2 and P1-3 to P1-4. Check for a constant 12 .6 VDC across P2-1 to P2-5 and P2-2 to P2-6 and P2-3 to P2-7.

 

user21

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Thank you! I'll try that and report back when it happens next time. Since it doesn't happen very often, is there anything else I can look for depending on what I find?
 

rickgburton

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The power supply board supplies the power for the AC loads and the DC loads. It's always best to start at the beginning.
 

user21

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Seems reasonable! Below are the requested readings.

Power board:
P1:
1 2 3 4
1-2: 120VAC
3-4: 120VAC

P2:
X 7 6 5
4 3 2 1

5-1: 12.6V
6-2: 12.6V
7-3: 12.6V
7-4: 12.6V

Main board:
P1:
1 2 3 4

1-2: 120VAC
 

user21

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Location
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Also, would you happen to know if there is a service manual available from KitchenAid? It would be tremendously helpful to understand the wiring diagram! :) Thanks
 

rickgburton

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If those voltage measurements were taken when the machine stopped cooling and everything turned off, here's the part you need:



The tech sheet has the wiring diagram and the service manual will have the same thing. It won't teach you how to read a schematic or diagram. What part is hanging you up? Maybe this will help:
 

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user21

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Sorry, I should have more clear! I can't seem to find any documentation such as a service manual for this model, which makes this troubleshooting very difficult. I was hoping you may know where I can find it!

Yes, the measurements were taken when the fridge failed. Thank you for suggesting the replacement part. Based in your recommendation, are you thinking that the power board is okay, and there may be something wrong with the main control board?

I was hoping to isolate some of the other sensors/components before replacing the main board. It seems like it's trying to switch into a mode, but is not getting the correct feedback.

Would you happen to know what the purpose of the valve that it's trying to energize every second and what the feedback mechanism for that circuit?
 

rickgburton

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Correct, The power board is supplying the main board with the correct AC and DC voltages so the problem is with the main board. The compressor, condensor fan motor, display panel, and lights don't work when this happens but they all work after unplugging the machine and then restoring power. So unless you think all those components failed and became intermittent at the same time you can assume they are all good. The thermistors/Sensors are variable resistors that supply information to the main board. They don't control any of the components. Your tech sheet is located under one of the door hinge covers. That will have your wiring schematic and diagram.
 

user21

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Messages
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Location
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I opened up the door hinges on the top but no luck finding the diagram.

You are definitely right, a broken sensor, however, can easily alter the behavior of the control board state machine. Just before ordering a $300 board that I can't return, it would be nice to make sure it was not something else. The board firmware after some time clearly gets itself into some recovery mode where it's waiting for feedback from a sensor and is attempting to energize a small valve by the compressor fan. If I could figure what the valve is, then I may have a clue on what else to check, and assuming I can find a service manual, if there are any diagnostic tests that may help obviate the problem.

As always, appreciate all your help!
 

rickgburton

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user21 said:
If I could figure what the valve is,
Your machine is a sequential cooling dual evaporator. It uses two separate evaporators and cap tubes. The 3-way valve directs the refrigerant flow to either the freezer evaporator or refrigerator evaporator which ever compartment is calling for cooling. Refrigerant flow is directed through only one evaporator at a time. Thus the word sequential. This is for a different machine but I believe the first five test are the same.
WRV986FV.jpg

To enter Service Diagnostics: Press SW1 and SW2 simultaneously for 3 seconds.

Release both buttons when you hear the CHIME indicator.

The display will show 01 to indicate the control is in test 1 of the diagnostics routine.

Each test must be manually advanced. Press SW5 to move to the next test in the sequence. Press SW4 to back up in the sequence to the previous test

Each step is displayed in the two digits of the dispenser user interface display. The step results are displayed in the two digits on dispenser user interface display 2 seconds after the step number is displayed. An amber order filter light will be shown to designate that the step number is being displayed A red replace filter light will be shown to designate that the status of the step is being displayed.

To exit Service Diagnostics Press SW1 and SW2 simultaneously for 3 seconds, disconnect the product from power or wait 20 minutes. Following the exit of the diagnostic mode, the controls will then resume normal operation.

Service Test - 1: FC Thermistor
The board will check the resistance value of the thermistor and display flashes results on the Temp display
01 = pass 02 = open 03 = short.

Service Test - 2: RC Thermistor
The board will check the resistance value of the thermistor and display the results on the Temp display
01 = pass 02 = open 03 = short.

Service Test - 4: Compressor/Condenser Fan Motor/ Evaporator Fan
There will be a delay of 3 seconds before start of Sub Step 01. NOTE: Each test is timed and will automatically proceed to the next step. User will not be allowed to exit test. If exit is attempted, an invalid chime will sound. Control the sealed system loads by selecting SW3
01 = initialize dual evaporator valve in home position (4 min.)
02 = close both RC and FC evaporator valves (1 min.)
03 = turn compressor on (1 min.)
04 = keep compressor on. Drive the valve to RC position and turn RC fan on
05 = keep compressor on. Drive the valve to FC position and turn FC fan on

Verify airflow from the evaporator fan.
NOTE: Advance quickly through Service Test 4 to keep from locking in. Once locked in, you cannot exit, and must wait approximately 10 minutes.

Service Test - 5: Compressor Status/Speed
Initial Display 02 = Minimum speed
Depress SW3. Display = 03. Compressor ramps up to maximum speed. When maximum speed is reached, 01 is displayed.
Depress SW3. Display = 04. Speed ramps down from maximum to minimum speed. Display = 02.
 
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