Patent ID: 6118099
Filing Date: 2000-09-12
Classification: B60H

Abstract:
A heating control system for heating an interior compartment of a motor vehicle, the heating control system comprising:an air-flow structure defining therein an air passageway to the interior compartment;a blower for forcing air through the air passageway towards the interior compartment;a reversible heat pump system having an electric compressor for compressing a refrigerant, an outside heat exchanger for transferring heat between an outside environment at an ambient temperature and the refrigerant, an inside heat exchanger for transferring heat between the refrigerant and the air flowing through the air-flow structure, a refrigerant flow switching device for switching the flow of refrigerant to provide a cooling mode and a heating mode, and a flow management center for providing pressure reduced refrigerant to the inside heat exchanger and the outside heat exchanger;an electric heater arranged in the air-flow structure for generating electric heat for directly heating the air flow directed to the interior compartment;a controller for determining a heat pump gain representing a heat pump heating capacity and for determining a system gain representing a required heating capacity for obtaining a desired interior compartment temperature, said controller modifying the heat pump gain based upon changes in the ambient temperature, and said controller selecting the reversible heat pump system for supplying heat to the interior compartment when the heat pump gain is substantially equal to or greater than the system gain.