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isolating 2 zone control valves from the T-T connections on a new boiler

pianovotpianovot Posts: 1Member
Just installed a new Weil-McLain CGa-5 boiler. Using two (ancient, but working with previous boiler) White-Rodgers zone valves - 24 vac. There are two red, one white, wires coming off them to attach to the boiler. I caught the repeated warning in the boiler instructions to NOT attach the 3 wire valves directly to the T-T leads. It stated I must have an "isolation relay" between the two. When I search to buy one, I am faced with telling them exactly what kind of relay I need. Can you help me to know exactly which kind to ask for? Voltage... DO/DC... or something different? My knowledge is obviously limited.
Thank you for any reply; without heat right now!


  • STEVEusaPASTEVEusaPA Posts: 3,061Member
    Just a RIB, found at any supply house
  • Solid_Fuel_ManSolid_Fuel_Man Posts: 1,598Member
    RIBU1C, it will accept the 24vac you have running the valves. Post back when you have it, and get some pics of the valves.
    Master electrician specialising in boiler and burner controls, multiple fuel systems, radiant system controls, building controls, and universal refrigeration tech.
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