Modified heat pump

Abstract

A modified heat pump (12) comprises a closed circuit around which a refrigerant fluid is circulated, a plenum chamber (13) and an auxiliary heat exchanger (16). The closed circuit has a compressor, a condenser, an expansion valve and an evaporator. The evaporator is located within the plenum chamber (13). The plenum chamber (13) also has an inlet (14) adapted to receive a fluid heat source medium and direct it over the evaporator, thereby to extract heat from said medium, and an outlet (15) adapted to receive cooled medium expelled from the plenum chamber (13). The auxiliary heat exchanger (16) is located between the inlet (14) and the evaporator, and is adapted to warm said medium prior to it passing over the evaporator.

Dependencies are inferred from the claim text.