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Boiler continues to run when thermostats are satisfied

I have three zone boiler and the boiler comes on when thermostats are satisfied what's wrong?

Comments

  • BobC
    BobC Member Posts: 5,502
    Does the boiler heat your domestic hot water?

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • tkmoore1955
    tkmoore1955 Member Posts: 3
    No I have a hot water heater
  • delta T
    delta T Member Posts: 884
    How old is this system, if its old enough it may be a 'hot' boiler. Still see a few of them around.

    pics would be nice.
  • GW
    GW Member Posts: 4,832
    If it's new enough it may have wwsd. The wall folks like pictures, because most of this stuff is kinda technical.
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    gary@wilsonph.com
  • unclejohn
    unclejohn Member Posts: 1,833
    You may just have a stuck end switch. Smack the zone valves.
  • 4Johnpipe
    4Johnpipe Member Posts: 485
    If it's an older boiler it may be the aqua stat relay or boiler control. Some have a preset low limit some can be adjusted.
    LANGAN'S PLUMBING & HEATING LLC
    Considerate People, Considerate Service, Consider It Done!
    732-751-1560
    email: langansph@yahoo.com
    www.langansplumbing.com
  • Paul48
    Paul48 Member Posts: 4,469
    Agreed...whether you're using it or not, the boiler may have a domestic coil and triple aquastat.
  • Robert O'Connor_12
    Robert O'Connor_12 Member Posts: 728
    Are all three zones heating, or just one? do you have zone valves or circulators? I recently had a job where this happened. Drove me crazy. turns out the 3rd floor thermostat wire ran into an attic where squirrels were chewing on the wires. Wires touch, your heat doesn't turn off.

    Robert O'Connor/NJ