Wall hung boiler parts 1.diameter:20mm 2.Reverse way:motor drive 3.Working violtage :220V 4.Sensor voltage: DC5V Bithermal Hydraulic Block Gas Boiler Parts Specification for Bithermal Hydraulic Circuit: The hydraulic sets include hydraulic valve,by-pass valve,circulating water pump and water flow sensing unit, temperature sensor, etc. It is used for wall hung boiler (combination gas boiler) ...