1.PCBA design for heat pump water heater 2.Punctual delivery 3.Short circuit protection PCBA Design for Heat Pump Water Heater 1. Auxiliary power function ... heating temperature, timing heaing time, input water leavel, timing input water time.4. Water level detecton, AC/DC valve control input ... optional, waterproof protection, circulating pump failure detection. PCBA Design for Heat Pump Water Heater