Patent ID: 7640761

Claim:
A heating, ventilating and air conditioning system comprising: an indoor unit including a motor driven fan for circulating air to and from an enclosed space, said fan being driven by a variable speed electric motor, at least one heat exchanger disposed in a flow path of air circulating through said indoor unit; and a controller operably connected to said indoor unit including a programmable microcontroller operable to provide pulse width modulated signals to a motor control unit for said motor, said controller including one of installer and user selected values of motor speed for controlling airflow through said heat exchanger to provide at least one comfort parameter sensed by said user; wherein the controller is configured to cause operation of the motor to provide a flowrate of about twenty percent to about fifty percent of a maximum flowrate during a pre-run delay period, the controller is configured to cause operation of the motor to provide a flowrate of about fifty percent to about eighty percent of the maximum flowrate during a short run delay period that follows the pre-run delay period, the controller is configured to cause operation of the motor at substantially the maximum flowrate after the short run delay period, and the controller is configured to cause operation of the motor at about fifty percent to about sixty-five percent of the maximum flowrate during a run-on cycle after the motor is operated at substantially the maximum flowrate.