A heating control method is provided for a multi-stage heating system
including a heating circuit having a compressor, a condenser and an
evaporator. An auxiliary heater is provided that is selectively
controlled independently of the heating circuit. During a heating cycle
in which the ambient outside temperature is greater than the balance
point temperature associated with the operation of the heating circuit,
the auxiliary heating circuit is normally prevented from operating.
However, if the heating requirements are not satisfied after a
predetermined time or the compressor is non-functional or operating
improperly, the auxiliary heater is enabled.