Electric Central Heat must power off and back on

[Trying2FixIt]

My electric central heater seems to work when the temps are not too low. But during the night as the temp drops the heater does not cycle on. If I power it off and back on once, or several times it runs and raised the temp in the house. Last night I replaced the thermostat, once the temp raised up to 70 it automatically cut off, when I raised the temp the heater would not cycle on. If I turned it off and back on it kicked on.
Obviously it was not the thermostat that was bad. What are the next things I should look at on an electric central and air unit. Which, bty, the air works fine.

[Minesbroketoo]

Ditto

I have the exact same problem, intermittently the heater just doesn't come on. I have to kill the power at the main breaker and then it will work.

Did you figure anything out yet?

I have a feeling it's the relay, but I haven't had a chance to look yet.

Thanks and good luck

[paul52446m]

It sounds like your heat relay is not making at times. If you can check your wiring, then check for 24 volts at the heat relay. if you have 24 volts then it should start the heat.
If you have 24 volts and the heat does not come on then change that relay. later paul