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flustered with weil mclain uo-3 and riello f5 burner

BST Member Posts: 1
i am a well established hvac company in new england south of boston and very flustered. i recently changed the oil boiler in my own house with a weil mclain ultra oil fired boiler and a riello f5 burner. it has been up and running for 2 months now. when i installed the burner i set it up exactly as riello recommends. i have installed several of these and never had any problems with them. what happens is the boiler comes on and runs great after about a minute of running it starts to spudder and chug really bad. it seems to me like their might be an issue with fuel supply so i changed the filter, nozzle , and pump strainer which was all new upon installation. i have made sure that the electrodes are properly set and there is plenty of fresh air. the boiler does not shut down on reset at all. it almost sounds like air in the oil line but i have bleed it several time with no problem. all fittings and stuff are tight like they should be.  if anyone has had this problem or can guide me in a helping direction i would greatly appreciate it. thanks   

brian in massachusetts


  • R Mannino
    R Mannino Member Posts: 440
    What Kind

    of combustion numbers did you get?
  • meplumber
    meplumber Member Posts: 678
    Check the nut on top of the oil valve solenoid.

    Just something else to check.  sounds like an oil delivery problem to me.
  • billtwocase
    billtwocase Member Posts: 2,385
    touchy boiler

    I have them with NX, and they will drive you nuts. What is your draft readings? Pump pressure?  Nozzle? Don't be afraid to boost the pressure. Personally I would have a .75 60W with at least 175 PSI. Tune and test from there. Also there should be a blanket on the bottom, and I have also added target walls on those boilers. Good luck.
  • Al Letellier_21
    Al Letellier_21 Member Posts: 402
    U)-3 issues

    Why haven't you contacted Weil about these issues, or have you? Their NE office is close to you and I have never been refused assistance on issues like this, nor have I ever not had the issue remedied when calling them for tech support.
  • heatboy
    heatboy Member Posts: 1,468
    Have you checked.....

    ..... vacuum and pressure readings once the unit starts acting up?  Put your Riello pressure and vacuum gauges on the fuel unit and see what the readings are.  Without doing those two things, you're in the dark.

    There was an error rendering this rich post.

This discussion has been closed.