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LWCO distance between primary and safety V903

I have a burnham V903, when it short cycled tonight I noticed that the primary LWCO is set about 2" higher than the safety. Is this correct or was it set to high during the install?


  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,844
    edited January 2023
    You have 2 LWCO and one is manual reset and the other is auto reset. The higher one should be the auto reset the lower one should be the manual reset.

    Is your boiler cycling on the LWCO and you believe it is too short of a cycle between turning the burner OFF and when the burner goes back ON?
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics