I woke up early one morning (today) smelling something hot. For a long time I couldn't figure out what it was. But it seemed to smell the strongest when I would pass an air duct. I then went to the closet where the inner portion of the "Colman" central unit was located, and noticed it was quite warm in there. I felt around for where the heat strips might be and I felt an area that was heavaly insulated, and it was very hot. The fan wasn't running at this time. I wondered if that might be the problem. Then I noticed that the thermostat display (Hunter programable model # 44402 002) was blank. I swapped the batteries and the display fired back up. I reprogrammed the thermostat, but it still doing the same thing. I then placed the fan on manual to see if there was a problem with the fan. The fan runs great. I have just started running the heating side of this unit this year because of the high price of natural gas. I ran natural gas the past five winters. So I am a little rusty as to how this thermostat operates. The problem may be due to the thermostat setting, it's set to "heat", rather than "auto". I dont really know. That's just a guess. Would it matter ? You still dont want the heat strips to come on untill called for. Isn't that right ? If the thermostat is set on "heat", is it calling for heat all the time, or just when the temperature falls below the desired room temperature ? The fan was set on "auto". I am unable to tell you anything about the central unit other than it is a Coleman brand. Some 20 -25 years old, I beleive. If left unattended, and no fan running, can these heat strips get hot enough the burn a house down ? With the thermostat in "auto", the heat strips are still getting hot and the fan is still not blowing.

 

My first question is, is the programmable thermostat one *specifically* made for heat pumps? They are not interchangable for regular ac/furnace thermostats (and they cost more too, go figure..).

The heat strips should only come on when there is a significant difference between the air temp and temp setting on the thermostat (as I understand it), or if it's just too cold outside to be able to maintain the heat with just the heat pump system alone.

For example, if it's 68 in the home, and you set the thermostat to 80, it's going to call on the heat strips.. If you set it to 70, it probably won't. Most heat pump thermostats have an indicator that shows when the heat strips are being used (usually marked as 'Emergency heat').

In any case, the heat strips should NOT be on if the fan isn't running, that's a fire waiting to happen at worse, or burning out the strips at the least.

 

Do you have a heat pump or just electric furnace. When and why a new tstat?? How long ago? With tstat turned to heat and fan to auto pushed down are they on?? If so pull the R wire off tstat. Do they shut off. If not check heat relay for the strips in the unit next.If they do check tstat wire.


ED

 

The Coleman is not a heat pump. It's a split unit central air conditioner with heat strips. When the programmable thermostat was purchased was around 10 years ago. Why it was purchased ? Because I wanted it. Nothing wrong with the old standard thermostat. I just wanted to be able to automatically set the temperature lower at night when I am sleeping. I dont know if the thermostat was made for a heat pump or central air conditioner. I didn't know it made a difference. I do know it worked quite well for several years. I'll check "Hunter's" web site (if they have one) for that information today. I haven't yet checked the relay. I'll do that today also. The relay will be inside with the heat strips, correct ? I finally hade to remove the fuse to power down the heat strips.

 

If you take the "R" wire off the stat and the heat strips are still energized the heating contactor is probably stuck.