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In floor solenoid water valve failed?

gtboss Member Posts: 2
I have a 10 year old hot water HYDRO-AIR 4 zone heat system. 3 of the zones have radiators with small 120v fans and are working fine. #4 is in the master bathroom only, under a stone tile floor that is not getting warm. I switched a 150 watt light bulb on/off to test the thermostat. The load for the thermostat is a 120 vac 70 ohm water valve under the floor tile? or behind the baseboard? which I believe has died. The pipe for the floor heater is 5/8 inch od transparent flexible plastic. Do you agree or am I missing something else? If not, what solenoid water valve would be best to replace it? Thankyou.


  • hot_rod
    hot_rod Member Posts: 20,790
    You need to find the valve, power it, see if it opening.
    Generally you see zone valves not solenoids in hydronics.

    Might be a mixing valve in the floor zone also? They usually run lower water temperature to tile floors.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • mattmia2
    mattmia2 Member Posts: 8,866
    What makes you think it is 120v? Most hvac controls are 24vac. Things that would be 120v usually would only be an installed electric heater, electric radiant heat, or maybe a heat lamp or heater in a bath light fixture.
  • gtboss
    gtboss Member Posts: 2
    Thanks for the help. I'll start with the baseboard this weekend.
    EBEBRATT-Ed Member Posts: 14,534

    If the fan is 120volt and the thermostat is 120 volt than the valve may be as well