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Short in Honeywell TH8110R1008

Le JohnLe John Posts: 166Member
edited February 11 in THE MAIN WALL
Does anyone have a contact number for Honeywell Thermostats. I awoke to a very warm zone. My Lochinvar Noble was running at 10% firing rate and the temperature was 76 although the thermostat was set to 68. Looks like the back plate that holds the thermostat to the wall has a short in it. When I press on the terminal strip it stops and starts again.

I called TACO and they help troubleshoot the issue back to the thermostat. So I removed the base and installed another thermostat (Honeywell Pro 2000) and did not have the same issue. Boiler only fires on a call for heat. Its a great thermostat so I'd like to get a replacement base.

Any ideas


  • Le JohnLe John Posts: 166Member
  • ChrisJChrisJ Posts: 10,503Member
    If pressing on the board fixes the issue it's likely a bad solder joint, not a short.

    That said, I'm betting you'll be buying an entire thermostat. I don't believe they sell just the wall plate.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • JUGHNEJUGHNE Posts: 6,533Member
    Some HW stats have a 5 year old is this one?
  • Le JohnLe John Posts: 166Member
    Thanks @ChrisJ - So what would this be then. White to White Blue to Common and Red to Red. In the picture the Yellow light is energized on zone 4. Is this a short or a bad solder joint.
  • pecmsgpecmsg Posts: 1,135Member
    Cheaper and easier to get a new stat!
  • Le JohnLe John Posts: 166Member
    JUGHNE said:

    Some HW stats have a 5 year old is this one?

    @JUGHNE It's 2 years old.
  • JUGHNEJUGHNE Posts: 6,533Member
    I would guess that the relay that closes R-W is stuck......if effect a short across the relay/switch.
    If you try to fix it, then any warranty would go away. IMO

    Find the paperwork on it and maybe the warranty terms are shown there.
  • Le JohnLe John Posts: 166Member
    Special Shout out to supply as-they are going to replace it - turns out the Honeywell Stat is warranted for 5 years as @JUGHNE mentioned.
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