a/c will not do anthing with out power from the fan.
the a/c amp detects fan loss and shuts down a/c
air-conditioner-repair
the heater will not make heat with out fan air. so the heater will be dead too.
so the fan.
here is more info on the fan.
see next post.
above post shows how the fan , circuit , intererupts AC ops.
you