Hi,
I have a Rheem forced-air electric heater which is at least 15 years old but probably more. I know it's not a 90%, but I don't know if it's 80% or natural draft.

Sometimes it works fine, but many nights the blower will turn on but not the heat, so I'll wake up to a cold house. Turning it on and off a couple of times by setting the control temperature below and above the air temp usually causes the heat to actually kick in but this doesn't always work.

I had a technician come and he replaced an obviously bad limit switch. He didn't have the right one on hand so this limit is only connected to one heating element and he is getting a different limit. However, I don't think this will solve the problem since the same thing is happening with this temporary limit and I still have to turn the thing on and off to get the heat to turn on.

Any ideas? It's electric so I don't think it has an ignitor. I can't think of any reason why turning it on and off would do anything.

Thanks,
KM

If you have electric heat only, not a gas furnace or a heatpump the heat is brought on by a sequencer it works off time. The blower comes on first and then your heating elements. When it shuts off the elements shut off first and then the blower about 90 sec. later. It sounds like you have a bad sequencer.

It sounds to me like a relay or contactor going bad. It could be managing to make once every several tries. You might check the control voltage. You should have 24 volts between the R terminal and com.