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FREE Member Posts: 1
Hello, I have a Laars EBP about 5 years old, The boiler constantly cycles and rarely shuts off. Even when no call for water ! It shakes and rumbles the pipes and then reads F-4. Then it just starts up again and cycles. My water is hot but there is something definitely wrong with this design. Over years Ive had control panel changed, igniter and one flow sensor....Should I just get rids of this unit? 


  • Brad White
    Brad White Member Posts: 2,398
    Have you

    contacted Laars and what did they say?
    "If you do not know the answer, say, "I do not know the answer", and you will be correct!"

    -Ernie White, my Dad
  • Ironman
    Ironman Member Posts: 7,400
    F-4 Code...

    Means supply sensor error. Two things to check:

    1. From what you describe, it sounds like no water circulation thru the boiler. Look for a bad circ. pump or valve closed. It's also possible that the heat exchanger needs de-scaling. Is there sufficient water pressure on the boiler? should be 12psi min.

    2. The sensor itself could be bad. Should measure 10k ohms @ 77deg.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
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