Tekmar Zone Control Valve - 3 Zones w/ Priority

The Zone Valve Control 303V connects up to three thermostats and operates zone valves to provide heating to a zoned hydronic heating system. The 303V operates a system pump whenever a zone valve opens. Zone 1 can operate either a zone valve or a circulator to provide heat to an indirect domestic hot water tank with optional priority over zones 2 and 3. The 303V includes optional exercising to prevent circulator seizure when not in use, and optional post purge operation of the domestic hot water tank to maximize energy savings. The 303V provides a RoomResponse™ signal to modulating-condensing boilers to optimize comfort while improving boiler efficiency. Features CSA approved RoomResponse™ signal, compatible with all low voltage thermostats Two spare fuses included Fuses protect transformers and pumps LED for each zone, priority, end switch and RoomResponse™, away signal shared between tekmar thermostats Four ground screws, Top, bottom and back conduit knockouts Compatible with 2, 3 and 4-wire zone valves, ...