EPH Priority Hot Water Pack - PDHW - C00P-221981Working with OpenTherm, this PDHW control pack comprising of 1 no. CP4 RF Room Thermostat, 1 no. CP4 HW Hot Water Thermostat, 2 no. 2 Port 22mm Motorised Valves, and a wiring centre. This pack ensures higher efficiency with lower demand on the boiler. Allows flow and return temperatures to be reduced thereby increasing the efficiency of the heating circuit Lower flow and return temperatures ensure the boiler operates within its condensing range.