Constantly Running Freezer -20 deg F

Yes, that is model number with the extra F in there. I adjusted the original question. I do have a DMM and I will check that tonight when I get home. What does a tech sheet look like? I have had the kick plate off before and never saw anything however I was not looking for it either.

@poeller13 ,

Usually it is some papers in a plastic sleeve, but if you've had the plate off you would have seen it.

I'm only guessing this as that is where it was on other frigidaire models

You may just have to test the thermistor to see if the resistance changes when you alter the temperature around it.

Sometimes just by holding it in your hand and warming it you can see the resistance change if you have the meter across it at the time.

Try contacting the parts place where you got it from and check if they know the values of it at 32F and 68F. Worth an ask anyway.

Thank you very much. I appreciate it very much. Are these the only two things that would create a problem like this? Do you think that there is a chance that it could be the main board? I just don't understand how this issue is happening logically.

@poeller13 ,

The electronic control board - door part #151 controls the temperature as indicated by the thermistor and also the auto defrost cycle timing i.e. when to start the cycle and when to stop (stop indicated by the defrost thermostat) and to restart the compressor.

If the thermistor and the thermostat test OK you may have to look at the control board

If the compressor is continually running you may have to also check the wiring from the thermistor back to the control board as the compressor should stop when the set temp is reached. This may be a bit hard during the day as a lot depends on how often the door is opened letting in the warmer air (or letting out the cold air if you like), so the temp may not be stabilizing at the set temp, so maybe check first thing in the a.m. to see if the compressor is stopped as the door should be shut all the time overnight stabilizing the set temp.

Don't know the timing for the auto defrost but with most makers it is somewhere once every 8-12 hours and the compressor and evaporator fan should be stopped for about 15-25 minutes to allow the defrost to occur. This time is usually designed to allow the ice to be melted but not for the food to even begin to thaw

The temp is allowed to rise to 32F in the freezer to help the ice on the evap unit to melt and drain away.The melting is sped up by turning on the defrost heater.

When the temp reaches ~32-33 F the thermostat operates to tell the control board to end the defrost cycle and start the compressor and evap fan again to drive the temp back down

OK. That is what I am thinking. I tested the thermostat and thermistor last night and both seem to be ok. I was concerned that that was a connection issue with the defrost thermostat too so I hard wired it in. The compressor is definitely continually running and it never goes into defrost mode. I know this because there was two days where the freezer was operating properly. I was able to see that on the temperature logger. I could see the temp fluctuate (by a degree or two) then go into defrost mode and then come out and go back to regular temp. Then all of a sudden the temperature drops and "pegs" at that low temperature (because the compressor never shuts down). It is almost like the control module is all of a sudden not seeing that the freezer as gotten to temp. I wish that I could attach the temperature graph. It is very clear where the freezer is working properly and then when it goes haywire.

Thank you very much. I really appreciate all of you help. Need to decide on new control board.