Insulate behind thermostat?

[ripsnortMN]

I have a modine hotdawg with a wall mounted thermosta just to the left of the unit. When I set the the thermostat to 70 degrees it wont shut off until 74-75 degrees.

My buddy says his did this and he had to "insulate" behind the thermostat. He says the thermostat is reading the cold wall instead of the air temp. I dont have a hole or anything in the wall. The thermostat is just mounted to the drywall.

Have you guys heard of this?

 

[tcianci]

Oh yeah, absolutely! I had a thermostat (big bukly electric heat job) mounted in an electrical box in an un-insulated wall, the thing was never right! I moved the T-stat to a more central location mounted to one of my garage cabinets, no where near the the wall and it tracks the temperature perfectly now. You may also want to consider mounting the T-stat further away from you heat source so it can better sense the actual temp in the room. If it is up high and near the heater it is exposed to the hottest air in the room and other places in the room will be cooler. That actually may be your issue...is the thermometer you are using right at the T-stat or somewhere else in the room?

 

[hydramatic]

cheap mercury tube stat`s are off 3 deg either way..

 

[ripsnortMN]

Well guys I just put some pink rigid foam behind the thermostat and it seems to shut off at 70 where I set the thermostat at. The thermometer im using is right next to the thermostat. Its a cheaper non mercury thermostat so it doesnt have a built in thermometer on it, just the left to right sliding dial.

The heater is mounted in the corner aimed at the corner across from it, diaginally. So the thermostat is about twenty feet to the right of the heater, out of the heat path about four feet off the floor.

I guess it wont tell me to much until it gets a lot colder outside.