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2 zone valves one thermostat........Can this be done.

Hello All,
I am doing a rewire of a squirrels nest of wiring. I am not sure how many hands have been into it. I have some Honeywell zone valves the ones with the 5 screws...2 for end switch and the rest for transformer and Tstats. And one Taco with the 3 screws. Someone prior to us had 2 zone valves on the first floor zone and apparently was trying to run 2 zone valves on the one tstat. The homeowner took the wires off the Honeywell I guess because it was just giving heat when non was wanted.......that is the best he can remember. I want to put the 2 on the one tstat. One is the Honeywell and the other is the Taco. ....Any Ideas???
Thanks Paul


  • Richtdow
    Richtdow Member Posts: 22
    That sounds like a mess. The correct answer in my opinion would be to pipe everything on the first floor to one zone valve or install a second thermostat and control the first floor with two zones. I like option 2 best.

    If I were to try to run two zone valves from one thermostat, I wonder if you couldn't run the thermostat through its own junction box and wire two outs, one to each zone valve relay. This should open the zone valves simultaneously when the thermostat calls for heat. So basically you'd have the thermostat wiring going into the box and then two of each wire coming out of the box and into your relay where the thermostats wire into.

    Does it sound like something like this could work with your system?