Patent ID: 8011197

Claim:
An HVAC system comprising: an evaporator, a condenser, and a compressor connected in a closed loop refrigerant system; and a control system to control the closed loop refrigerant system, the control system comprising: a controller having a plurality of output connections capable of being electrically connected to a compressor, the compressor being electrically connected to the controller by at least one output connection; a load sensing circuit and a processor electrically connected to at least two of the plurality of output connections of the controller, the load sensing circuit being configured to generate a load signal for the processor for each of the at least two output connections connected to the load sensing circuit in response to a load being present on the at least two output connections connected to the load sensing circuit; the processor being configured to determine a type of compressor based on load signals from the load sensing circuit; and the processor providing instructions to configure the controller to operate with the determined compressor type in response to the type of compressor determined by the processor.