Inverter controller, method of operation thereof and field-installable retrofit kit incorporating the same

A method of operating an inverter controller, comprising:

• receiving conventional thermostat signals providing for a ventilation mode, first- and second-stage cooling modes and at least one heating mode;
• providing relay control signals for an inverter forward start relay, first- and second-stage cooling speed select relays and at least one heating relay based on the conventional thermostat signals;
• and
• providing an inverter forward start signal, an inverter high speed set, an inverter medium speed set and an inverter ventilation speed set based on the relay control signals.

An inverter controller kit, comprising:

• a thermostat interface configured to receive conventional thermostat signals providing for a ventilation mode, first- and second-stage cooling modes and at least one heating mode and provide relay control signals for an inverter forward start relay, first- and second-stage cooling speed select relays and at least one heating relay;
• and
• a module having:
• an inverter controller coupled to the thermostat interface and configured to receive the relay control signals and provide an inverter forward start signal, an inverter high speed set, an inverter medium speed set and an inverter ventilation speed set,
• a field-configurable blower speed selector coupled to the inverter controller and configured to select between a single-speed blower and a dual-speed blower, and
• a plurality of relays configured to receive and employ the relay control signals.