Thermador Column Freezer - Defrost Cycle ALL THE TIME

[Frank Griffith]

Hello everyone - I have a Thermador Column Freezer (T30IF).  A few weeks ago the defrost cycle changed such that it defrosts "too much" in that it would go into defrost cycle for a few hours several times per day.  As a result, ice quit making, and food became unfrozen.

This weekend I replaced the:

1. control board (p/n: 00667838)

2. defrost sensor  (p/n: 00617203)

3. thermsistor that measures the overall temp of the freezer (p/n: 00604180)

Also, during the repair attempt I took a reading of the heater itself and it was about 48 Ohms.

 

NOW: After the repair my freezer is in constant defrost cycle.  24x7 defrost cycle - no compressor, no freezing.

 

Is there a defrost cycle timer or something the control board is interfacing with that make be bad?  Do I have a bad control board?  Something else?  Very grateful if someone can help me.  THANKS!  Frank 

[jstew4880]

Got the same problem.. any solutions yet?

[16345Ed]

On 6/8/2020 at 8:31 AM, Frank Griffith said:

After the repair my freezer is in constant defrost cycle.  24x7 defrost cycle - no compressor, no freezing.

 

So liner must be melted and warped with heater on all day?

I doubt it’s in defrost. Probably compressor etc just not running. 
 

To verify clamp amp meter to defrost circuit. 

Edited July 13, 2022 by 16345Ed

[16345Ed]

It is possible new the boards need programmed. You’ll need to refer to service manual if board came with no instructions.