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Boiler turns off randomly

Northmen23
Northmen23 Member Posts: 2
edited December 2021 in THE MAIN WALL
I've had two different repair people out . No one seems to know what the problem is. the problem has gotten steadily worse. The boiler runs 1-10 minutes then shuts off. Not responding to thermostat. when i shut off electricy and turn back on it seems to work. then shuts down and wont work at all.

Comments

  • JohnNY
    JohnNY Member Posts: 3,290
    edited December 2021
    If it re-starts when power is cycled then the problem is in the ignition circuit.
    All the other operating controls would be unaffected by de-powering and the safety controls have a manual reset or thermal fuse. Say these words to the next person that tries to fix and see if they can narrow the problem down to an ignition module, flame sensor/spark ignition cable, or cracked porcelain on the pilot assembly.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
    Classes
  • Northmen23
    Northmen23 Member Posts: 2
    thanks for your help i will relay your message
  • Lance
    Lance Member Posts: 304
    May I add this observation. When a unit resets with power on/off/on, it can often reset limits, or the condition causing the failure has disappeared. Hi limit trip, did its job, energy off and it cools down. But won't restart because the mfg wants the unit to be checked by a person for the cause.
    But in 1 to 10 minutes something has to be found to find what is the trigger. A broke wire touching is most difficult to find especially when heat is a factor. Pressures and conditions need to be monitored to find out what is changing. Sure the light bulb may have failed on its own, but what if its the circuit, the fuse or a switch that decide to be off? Draft door switches, blower pressure switches, even the control modules themselves can cause problems. Isolate and troubleshoot, divide or bypass sections to find the cause. How about this for a problem: Spider web in a gas pipe, or sand in a gas main affecting combustion limits. Or how about a drop in gas pressure by the utility? By pass the thermostat wiring and wire a switch direct to troubleshoot. This is where a good diagnostic worker comes in handy.
  • kcopp
    kcopp Member Posts: 4,472
    What boiler is this? Gas? Oil? Brand?
    Model?
  • hot_rod
    hot_rod Member Posts: 23,379
    need to know what type of boiler. Mod cons for example will cycle like that if the main circulator fails. They heat quickly and trip high limit, cool down and repeat.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • mattmia2
    mattmia2 Member Posts: 10,924
    What kind of thermostat is it?
  • JohnNY
    JohnNY Member Posts: 3,290
    hot_rod said:

    need to know what type of boiler. Mod cons for example will cycle like that if the main circulator fails. They heat quickly and trip high limit, cool down and repeat.

    Yes, this. I made several assumptions about the boiler being an atmospheric, standard efficiency unit.

    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Consulting & Troubleshooting
    Heating in NYC or NJ.
    Classes