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LAARS Endurance Boiler (pre-2005 model) getting L.O. lockout code every few days

lleone Member Posts: 1
edited March 2015 in Gas Heating
I have a LAARS Endurance Boiler that runs fine for 2 or 3 days and then goes into lockout (L.O.). After I hit the reset button it will work for another couple of days before going into lockout again. This has been going on for about 3 weeks. Any ideas as to what might be the cause?


  • Abracadabra
    Abracadabra Member Posts: 1,948
    1 - poor combustion
    2 - poor flame sensor signal
    3 - inadequate gas supply
    4 - ignitor failure
    5 - blocked or contaminated air source

    I'd start by checking and cleaning the flame sensor rod
  • Jason_13
    Jason_13 Member Posts: 299
    What is the lock ut code?
  • Zman
    Zman Member Posts: 6,992
    Here is the manual.
    I would pay close attention to the venting. I have seen the inner pipe rot out and cross contaminate the combustion air. This kind of damage hard to detect and can create a CO poisoning risk to the occupants.
    I would not spend much money trying to troubleshoot and repair an endurance. 10-15 years seams to be the average lifespan for that boiler.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein