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Baxi HW problems

kcopp Member Posts: 3,899
Anyone have experience w/ Baxi 310fi combi boilers.? 9+ yr old unit.

I have a customer who is not getting hot water. Max they can get is 86F.
Boiler fires, runs for 5-10 seconds shuts down.... pauses for 5-10 fires...repeats


  • Tom_133
    Tom_133 Member Posts: 797

    It sounds like a diaphragm issue. Those units have a rubber diaphragm with a metal needle attached, so when water goes in the diaphragm swells pushes needle into micro switch that tells boiler to fire. Whats nice is you can see the process happen when you turn on the hot water, and if it's sucking the metal needle back in before the water shuts off then bobs you uncle. You can change the whole diaphragm cheap and easy. Since you are there check combustion in case I am wrong.
    Montpelier Vt
  • kcopp
    kcopp Member Posts: 3,899
    I followed the trouble shooting flow chart and that was not one of the things to look at.... I will now. TY.