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First Co 24VAQ3- want to add a Honeywell Zoning valve

robertm3
robertm3 Member Posts: 4
in Radiant Heating

Hi,

I have First Co, 24VAQ3 airhandler with hot water coil for heat. I am having issues with water cycle back through the coil. I’ve tried to flush and clean the check valve and nothing seems to work.
I just want to add zoning valve but I am not sure on the wiring. can the valve be wires directly into the 24 volt "W" leg on heating side of the Tstat or does this require a separate 24v transformer to operate the zoning valve?

Comments

  • Big Ed_4
    Big Ed_4 Member Posts: 3,005
    edited September 6

    A Transformer is needed to operate the zone valve motor , The zone valve end switch normally is wired to TT on circulator control …

    There was an error rendering this rich post.

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,400

    If the transformer is large enough (and it likley is) you can use the transformer in the air handler. Check the specs on the zone valve you want to use and look at the size (VA rating of the transformer) in the AHU. worst case is you install a larger transformer which is probably $20-$30.

  • robertm3
    robertm3 Member Posts: 4

    I bought a larger 24 volt 75VA transformer. The Honeywell zoning valve has 2 yellow and 2 Red. Can the yellow wires from the zoning valve be wired directly in on the “W” 24 volt heating wiring from the stat? And the red wirings just capped?

    Wiring diagram would be great appreciated.
    AHU from first Co has all relays.

    Thanks again

  • robertm3
    robertm3 Member Posts: 4
    image.png
    IMG_0619.jpeg

  • Big Ed_4
    Big Ed_4 Member Posts: 3,005
    edited September 7

    Always fuse 3A , The yellow are the motor leads , One wire to the common of the transformer , The load side (fuse) to thermostat R. , W to the other wire of zone valve ……

    There was an error rendering this rich post.

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,400

    disconnect "w" from the thermostat at the pump relay.

    Connect the removed w wire and connect it to 1 zone valve yellow wire and to 1 zone valve red wire.

    Connect the other zone valve red wire to the pump relay where the w was removed from

    Connect the other zone valve yellow wire to the pump relay coil brown wire.

    When the thermostat calls for heat the zone valve should start to open. When it gets open the two red wires in the zone valve make contact in the zone valve turning on the pump. The 2 yellows are zone valve 24 volt power to pen the valve. The two red wires are the zone valve end switch that starts the pump

    If the new transformer does not have a built in circuit breaker you should install a 3 amp fuse in the "R" Red wire coming from the transformer.

  • robertm3
    robertm3 Member Posts: 4
    IMG_0720.png

    Added new transformer with built-in 3 amp breaker. Going to clean up the wiring. 1 yellow to “W” from the tstat, 1 yellow to “C” brown. End switch Red wires, 1 Red going to yellow at AHU, 1 Red to Red at AHU. End switch turns on the pump relay.
    Thanks again for the help! Greatly appreciate it.

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