Abstract

A heat-pump circuit may include an indoor heat exchanger, an outdoor heat exchanger, a compressor adapted to circulate a working fluid between the indoor and outdoor heat exchangers, and an expansion device disposed between the indoor and outdoor heat exchangers. A monitor for the heat-pump system may include a return-air temperature sensor, a supply-air temperature sensor, and a processor. The return-air temperature sensor may be adapted to measure a first air temperature of air upstream of the indoor heat exchanger. The supply-air temperature sensor may be adapted to measure a second air temperature of air downstream of the indoor heat exchanger. The processor may be in communication with the return-air temperature sensor and the supply- air temperature sensor. The processor may be programmed to determine a working-fluid-charge condition of the heat-pump system based on the first and second air temperatures.

IPC Classes  ?

• F25B 30/06 - Heat pumps characterised by the source of low potential heat
• F25B 27/00 - Machines, plants or systems, using particular sources of energy
• F25B 49/02 - Arrangement or mounting of control or safety devices for compression type machines, plants or systems