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loud hissing radiators

Thanks for the advice! To downfire the boiler do I change the nozzle on the opil burner to a smaller capacity or do I need to change teh entire burner itslef?


  • Brother Crispin
    Brother Crispin Member Posts: 7
    hissing radiator vents

    How do I quiet those loud hissing radiators? My main is vented very well; at least three Hoffman 75's on each main and the system heats rapidly but some rooms have loud hissing rad. vents. HOwdo I cut down on the hissing and avoid alot of guess work and trial and error work?
    Thanks for the advice!

    Br. Crispin
  • Fred Harwood_2
    Fred Harwood_2 Member Posts: 195

    Loud hissing suggests that your boiler may be too big for the connected load. You might try downfiring the burner, and/or installing a Vaporstat.

    Also, ensure that your Pressurtrol and pigtail work; pigtails clog and allow excess pressure to build.
  • Fred Harwood_2
    Fred Harwood_2 Member Posts: 195

    Do you have access to and know how to use a combustion analyzer? If not, best to hire a pro.

    Also, you would need to know the EDR of your connected radiators and the EDR capacity of your boiler. You want the boiler energy input to be about 1.3 times the radiator output. You generally can downfire a boiler by about 15%, but you need to know some particulars to make it work. A professional can help you.
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