Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Lowest Stack Temp.

What was the lowest net stack temp. on oil fired unit you have ever encountered ?

Thanks

Jay

Comments

  • Steamhead
    Steamhead Member Posts: 17,333
    if it's less than about 325-350° F or so, it's too low, and can cause condensation in the chimney.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
    SWEI
  • Jamie Hall
    Jamie Hall Member Posts: 24,600
    Steamhead said:

    if it's less than about 325-350° F or so, it's too low, and can cause condensation in the chimney.

    And that condensate is truly evil stuff. Even with low sulphur oil, there is some sulphuric acid. Also nitric. Also carbonic. It will eat through almost everything!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • SuperTech
    SuperTech Member Posts: 2,389
    I saw 275 degree stack temp once. It was on a Buderus blue flame burner. It was crazy. I thought my Testo 320 was malfunctioning!
  • rick in Alaska
    rick in Alaska Member Posts: 1,463
    110 degrees on a condensing Adams Furnace.
    Have had quite a few common oil fired units under 300 degrees where I had to do things to get it over 325 though.
    Rick
  • Jamie Hall
    Jamie Hall Member Posts: 24,600
    A boiler or furnace which is designed to be condensing can indeed run well below 325, and do it safely -- provided it's properly installed. The materials are designed to take the condensate. If it isn't designed to be condensing, though...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England