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help needed to understand thermostat wires to Taco Zone Valve Controller

Le John
Le John Member Posts: 226
Good Morning all,
I recently gutted a small closet mechanical room to install a Lochinvar Noble Combi boiler. The boiler works fantastic (why did I wait so long to install this beauty) but my problem is with wiring for the three thermostats.


Garage thermostat J-Box
1 Red Wire
1 White wire. This white wire ties into a series of white wires that get tied together.

First Floor J-Box
1 Green Wire
1 White wire. This white wire ties into a series of white wires that get tied together.

Basement j - Box
1 Black Wire
1 White wire. This white wire ties into a series of white wires that get tied together.

Boiler room
1 Red Wire
1 Green Wire
1 Black Wire
1 White Wire - (Is this a shared wire among all of the thermostats?). I would have expected to see 3 white wires but there is only one.

I need to wire these wires to the Taco ZVC-404-4 Zone Valve Controller Box and Each Zone on the has three thermostats connections.
R
W
C (Common)

I'm lost as how to wire this?


I did a test an ran new thermostat wire to each zone and it worked fine (Each Honeywell zone valve opened and started the boiler. It did work with the old Taco Zone valve controller. (I should have taken pictures.)

I truly appreciate any guidance.






Comments

  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    Are all the zone valves in the boiler room, or scattered around the house?
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Le John
    Le John Member Posts: 226
    The zone valves are in the boiler room. The thermostats are scattered around the house.
  • I would try Scenario #1 first and then #2.

    Please see moniker below. : )


    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
    Solid_Fuel_ManLe John
  • Le John
    Le John Member Posts: 226
    Thanks for taking the time to respond @Alan(CaliforniaRadiant)Forbes . I believe i tried senario 1 but will try Senario 2 when I get home and post an update.
  • Joe Mattiello
    Joe Mattiello Member Posts: 704
    Alan's schematic should work. If your still not certain which wires to bring into R,&W on the Taco control, you can measure continuity across a thermostat that is closed, or calling for heat. bring those 2 wires into R & W and it should work fine if your thermostats do not require a common. Please contact Taco tech support at 401 942 8000, and they will walk you through it. hopefully this was helpful
    Joe Mattiello
    N. E. Regional Manger, Commercial Products
    Taco Comfort Solutions
    Le JohnErin Holohan Haskell
  • Zman
    Zman Member Posts: 7,561
    There are some names for people who run wires that way. None of them are suitable for this forum o:)
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
    Solid_Fuel_Man
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    I can think of a few.....
    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!
  • Perhaps, but you can sure learn a lot figuring it out.

    Some of the old wiring out there is hella' interesting.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • Le John
    Le John Member Posts: 226
    Hi @Alan(CaliforniaRadiant)Forbes . Scenario 1 works but when one stat calls all three zones open.

    Scenario 2 did the trick but in the end wound up running new thermostat wire for all three zones. I figured might as well do it now and be done with it. I'm using three Honeywell Vison Pro 8000 stats and can now connect them to the C connection on the Taco Box.

    Thank you again @Alan(CaliforniaRadiant)Forbes and @Joe Mattiello for your assistance - it was appreciated and @Erin Holohan Haskell for this site.
    Erin Holohan HaskellZman