I have a Rheem electric central heating system that when in the heat mode will not turn on the blower when the thermostat is in the auto position. The heat coils will come on but the blower will not come on unless I put the fan switch on the thermostat in manual position. I am trying to determine if the problem is with the thermostat or in the relay inside the heater compartment that turns on the blower. Any assistance will be greatly appreciated.

labman

Try and identify which wire from the thermostat controls the blower. There may be schematic at the air handler. Once you identify it, jumper it at the air handler to the R terminal. If the blower doesn't start up, it is the relay.

NorthernHeat

Has the stat been changed recently? If not, it is most likely, the fan relay is bad

hvac1000

I would say relay but with electric heat it could be the heat sequencer. One of the legs or tabs on the heat sequencer turns on the blower on a call for heat.

NorthernHeat

Depends on the model some Rheem's use a sequencer for the fan and some have a relay.