A method and controller for controlling the operation of a zoned climate control
system including a primary heat source, a secondary heat source, a cooling unit,
and a humidifier unit. The controller is configured to receive both heating demand
signals and cooling demand signals from a plurality of zone thermostats positioned
throughout the residence. Upon receiving a heating demand signal, the controller
operates the primary heat source to provide heat to the zone issuing the heating
demand signal. The controller determines whether the primary heat source satisfies
the heating demand signal within a maximum heating period. If the heating demand
is not satisfied within this period, the controller activates the secondary heat
source to supplement the heat being supplied by the primary heat source.