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Heat cycle reversed, what thermostat do I need?

TooHot Member Posts: 1
edited February 2020 in Thermostats and Controls
The valve in my radiator is open under a no power condition. That is the heat is on, it is open and flows hot water, when no power is supplied to the valve actuator. This is normal for radiator valves apparently.

My problem is my 2 wire wall thermostat makes a connection when under temp and opens the connection when over temp. Exactly the opposite of what I want/need. The result of this is the heat is on when the thermostat is over the set point and off when under the set point. What wall thermostat do I need to correct this? I need a NC (normally closed model). Problem is manufacturers do not label them or identify this in specs.


  • Ironman
    Ironman Member Posts: 7,376
    edited February 2020
    Use the cooling terminals : “R & Y”.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
    EBEBRATT-Ed Member Posts: 15,526
    Yes as @Ironman mentioned you could use a cooling stat. If your air conditioner is using the y & R terminals you can also use your existing stat with a relay to reverse the operation of your thermostat to run the heat from the R & W terminals but would require a little wiring
  • mattmia2
    mattmia2 Member Posts: 9,652
    /could also replace the actuator with a normally closed actuator, but the relay will be cheaper.
    HVACNUT Member Posts: 5,841
    Power close, spring open? What brand and model valve?