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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.

  • 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, unlimited zone expansion
  • Zone priority, priority override
  • Post purge, LED for each zone, priority, end switch and RoomResponse™/ul> Specifications
    • Ambient Conditions: Indoor use only, 32 to 122 degrees F (0 to 50 degrees C), RH less than or equal to 90 percent non-condensing
    • Enclosure Material: Cover: ABS plastic, Base: galvanized steel
    • Control Type: Microprocessor control, this is not a safety (limit) control
    • Enclosure NEMA Rating: NEMA 1
    • End Switch Relay: Boiler, DHW 24 V (ac), 5 A
    • Fuses: T5A 250 V slow blow, two spare fuses included
    • Mod Boiler Output1: 0-10 V (dc) 500 ohms min load impedance
    • Mod Boiler Output2: 4-20 mA 1 k ohms max load impedance
    • Power Supply: 115 V (ac) plus / minus 10 percent, 60 Hz, 11 A
    • Pump Relay: 230 V (ac), 5 A, 1/3 hp
    • Transformer: 40 VA at 24 V (ac), expandable to 80 VA with additional transformer M3069 (sold separately)
    • Zone Valve End Switch: 24V (ac)
    • Zone Valve Outputs: 24V (ac)
    • Agency Approvals: CSA C US
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