I have an Intertherm forced air electric furnace made in 99. Saturday, I noticed that it smelled really hot and the outside cover was very hot. We thought our blower motor had gone bad and called a repairman out who then on Monday replaced the motor which he said was bad, cost $400. Tuesday the same thing happened again, the fan wasn't working. We could get it to work my switching our thermostat off auto and onto the on position. We were told it was probably the relay which we replaced today. 4 hours later, same thing, fan is not wanting to come on. Once it sits for 2 to 4 hours it will work again. Any ideas as to what is going on.

I have an Intertherm forced air electric furnace made in 99. Saturday, I noticed that it smelled really hot and the outside cover was very hot. We thought our blower motor had gone bad and called a repairman out who then on Monday replaced the motor which he said was bad, cost $400. Tuesday the same thing happened again, the fan wasn't working. We could get it to work my switching our thermostat off of auto and onto the on position. We were told it was probably the relay which we replaced today. 4 hours later, same thing, fan is not wanting to come on. Once it sits for 2 to 4 hours it will work again. Any ideas as to what is going on.
Check to see if you have blockage (birds nest etc) in your exhaust which is located on your roof. Furnances have a limit switch and when it gets too hot inside the furnace the limit switch shuts down the blower.

If this was the problem would the heating coils still come on and the blower not operate? This is basically the same scenario when it stops working, coils heat up and blower doesn't run. We were wondering if it could be a thermostat problem?

To check and see if your thermostat is working swith it over to one of the manual setting (heat on, blower, etc.) and listen for a clicking noise which indicates that the thermostat switch is operating correctly followed by the blower coming on.

To double check things take the thermostat off the wall and connect both wires that come out of the wall that go into the thermostat. All you are doing by touching the wires together is by-passing the thermostat which should make your blower come on. If in fact the blower comes on then the blower is fine. If it doesn't turn the blower on then consider replacing the thermostat. Hope this helps eliminate a few issues.

First call the repair man back that took your money for not fixing your furnace. If you unit has a sequencer in it the blower activation section of that sequencer is probably defective. You may have one or more heat sequencers depending upon the model number of the unit.

There is also a transformer that converts house voltage to 12 volt. To identify this part look for 2 wires going into a square looking part with 2 wires going out. This square part also contains magnets. Usually this unit is located behind an enclosed metal box to protect it so a screwdriver will be required to gain access. You will need a volt meter to check this part. FYI my replament transformer part only cost me $15 so it's a cheap part to replace.

There is also a transformer that converts house voltage to 12 volt.

NOT 12 volts it is a 24 volt transformer.

Opps! Thanks hcav1000 I stand corrected.

We all make mistakes no problem.

Thank you for your responses, much appreciated. We replaced the thermostat but won't know for a while if this corrected the problem, if it doesn't, I guess we will have to call someone out to look at it, not the same guy as before though. He said he would charge us to come back out to find the problem. So again, thank you, will keep in mind sequencers and transformer if thermostat doesn't fix problem.