• Click here to access some of the presentations made during the 2022 National Rally

A/C thermistor

Geo

Active member
I recently had the inside cover off of my bedroom A/C to investigate poor airflow from one of the round vents. (That's a separate issue that I have given up on due to the collapsed foam duct work halfway from the unit to the vent.)
The question at hand concerns the thermistor hanging down into the return (intake) side of the unit. Is this a thermostat sensor or is it the freeze sensor. If it’s the freeze sensor then I need to “plug” it back into the fins, right?
 

BryanValRox

Well-known member
I recently had the inside cover off of my bedroom A/C to investigate poor airflow from one of the round vents. (That's a separate issue that I have given up on due to the collapsed foam duct work halfway from the unit to the vent.)
The question at hand concerns the thermistor hanging down into the return (intake) side of the unit. Is this a thermostat sensor or is it the freeze sensor. If it’s the freeze sensor then I need to “plug” it back into the fins, right?
Hey Geo,
Based on your description, it is most likely the freeze sensor as you call it.
The thermistor would be attached to/ insert into the fins to monitor the core temperature of the evaporator. Ultimately it gives feedback to the expansion valve and control the flow of refrigerant into the evaporator to prevent freezing.
Sorry to hear your duct work is more involved than you expected. Sure sounds like a warranty claim to me.
 

dwcfish

Well-known member
I had the same issue with the freeze sensor. You do need to be sure it is fully inserted in the fins. If after inserting, you turn the AC on and it is still freezing up you may not have it pushed in far enough.
 

Geo

Active member
Thankfully I have not noticed the evaporator coils freezing up. Attached is a picture of the sensor. I removed the thermostat from the wall and there is definitely NOT wires behind it from this sensor so it must be the freeze sensor. I do have an email pending with Alliance but it sounds like they are contacting Coleman about it.

AC - 1.jpeg
 

dwcfish

Well-known member
That appears to be the freeze sensor. If you look further up you will see where this plugs in and it should be - at least on mine it is - labeled Freeze where the wires are connected.
 
Top