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HONEYWELL STEAM ZONE VALVE

I HAVE A PROBLEM HAVE A VERY OLD HONEYWELL ZONE VALVE THE NUMBERS I GOT OFF THE VALVE ARE Z2045A 1038 24 VOLT 60 HZ I NEED THE WIREING DIAGRAM SO I CAN GET THE RIGHT TSAT THE OLD T87 HAD A RWB ON THE SUBBASE I THINK THE VALVE IS POWER OPEN /POWER CLOSED ANY INFO WOULD HELP

Comments

  • cid2
    cid2 Member Posts: 4
    V2045

    I believe it is power open/power closed. The original stat with RWB could work or you could use a relay connected to a heating only or cooling only thermostat, depending upon your application.

    If using a tstat with RWB....one side of the transformer (24 volt Blue) should be connected to R of the tstat. B of the tstat should be connected to the terminal on the valve actuator that drives it to open. W of the tstat should be connected to the terminal on the valve actuator that drives it closed. The common terminal of the actuator should be connected to the common of the transformer (24 volt Yellow).
  • V2045
    V2045 Member Posts: 1
    V2045 ? Answered

    HI,

    These are simple controls. Use any Honeywell PRO series thermostat and YOU MUST SET THE STAT for HEATING ONLY using the installer set up. R is common Blue to open the valve and W to close. Simple.
  • GBriggs
    GBriggs Member Posts: 15
    V2045?

    Just one more point in understanding series 20. Thermostat R terminal is wired to the R terminal on the valve. Thermostat terminal W is wired to the B terminal on the valve. Thermostat Y terminal is wired to the W terminal of the valve. The valve must have 24 volts at all times on TT.
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