Heat-pump water heater applied in bathroom

Proposes the basic concept of bathroom heat-pump water heater with heat recovery devices, and presents its constitution and flow diagram. Analyses its characteristics from lg p-h and T-s diagrams, and calculates its theoretical and practical COP values. The analysis shows that, compared with conventional electrical water heater, its maximum theoretical COP is 13.4 times over and it is able to reduce about 92.8％ of electricity consumption.