Heat pump for central heating - has refrigerator circuit with evaporator in air duct, with exhaust fan and heater

摘要

The heat pump for a heating system has an engine (5) driving a compressor (6) in a circuit with a condenser (7) which has a coil in circuit with the engine heat exchanger coil(10). The refrigeration fluid passes through an evaporator coil (9) in a duct (13) thrrough which external air is drawn by an extraction fan (12). This air is preheated by a heater (14) preceding he evaporator (9) and forming a unit with it, and which operates so as to increase the compressor output by permitting higher speeds. This heater, or alternatively an electric element. The duct includes a control flap (16).