... to water heat pump:1. indoor unit included 4 way valve, liquid storage tank, pcb, heat exchanger, auxiliary heater, pressure gage, ... easily transported units installed. Super cryogenic heating Optimized system design, ,also can work efficiently even in the ... and heat exchanger (316 stainless steel brazing type, high-efficient S&C, high-efficient heat exchanger tube), small volume, high heat enchanger, ...