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boiler shutting on and off when thermostat goes on

tariq1tariq1 Member Posts: 5
Hey guys, every time my thermostat turns on my boiler and pilot turn on and off. I have a Weil McLain gas water boiler. I replaced the relay switch and the problem still occurred. I have 4 zones and one boiler in my house. The house heats up but it just goes on and off many times as the heat is on. Also the green power light and the red light are on at the same time at times.


  • Tim McElwainTim McElwain Member Posts: 4,434
    Does this have a United Technology Integrated Boiler Control 1013-200 or is it a Honeywell S9300 Board? If the 1013-200 you have a green power light and then a series of Red lights TSTAT CIRC, LIMIT, PRESS SWITCH AND FLAME. Which lights are flashing when you are having this problem?
  • tariq1tariq1 Member Posts: 5
    Hi it's the united technology boiler control 1013-200 switchboard. D
  • warnowarno Member Posts: 229
    I don't know much about in home boilers but could it be something as simple as a dirty thermocouple? I know my forced air furnace will do that if the thermocouple is dirty. If gas fired boilers don't have this then disregard. Like I said I don't know much.
  • tariq1tariq1 Member Posts: 5
    I don't think I have a switchboard
  • Tim McElwainTim McElwain Member Posts: 4,434
    edited November 2016
    What lights are flashing on that 1013-200 board? Give me that and we can walk you through some diagnostics. Do you have a multi-meter? What is the Model number of the boiler? This boiler does not have a thermocouple it has a hot surface igniter.
  • tariq1tariq1 Member Posts: 5
    No lights are flashing on the board. The lights that are on are green and red. The green is power and the red light that is on means low water on the transformer I believe. Not sure if I have a multimeter. It's a Weil McLain gas -fired water boiler gold cga.
  • JUGHNEJUGHNE Member Posts: 7,861
    It sounds as if you need a pro to check things out.
    The simplest thing would be that your hot surface igniter (glow plug) will light but than not sense the fire and shut down the gas valve.
    That would be a first guess.

    There is a "Find a contractor" tag above on the Main Site.
  • tariq1tariq1 Member Posts: 5
    Ok thanks for the great information.

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