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Reducing mod/com output with multiple stage gas valve

BigRob Member Posts: 297
I need to serve some 6k loads and am exploring options. Has anyone experimented with this? I suspect it would run pretty lean.


  • SWEI
    SWEI Member Posts: 7,356
    Wouldn't even think of it

    violates pretty much every listing the boiler has and would expose me to unfathomable liability.  For loads that small, we use modulating electric resistance boilers.
  • BigRob
    BigRob Member Posts: 297

    I immediately regretted posting this. Why don't they offer more aggressive turn down in residential products? Multiple small fire tubes would be interesting.
  • Jack
    Jack Member Posts: 1,045
    You might look at

    The Rinnai Energysavers. Model EX 08 will modulate from 3-8 kbtu.
  • SWEI
    SWEI Member Posts: 7,356
    More turndown

    comes with more problems maintaining clean, efficient combustion.  Or has on existing burner designs. has the potential to change the game.
  • BigRob
    BigRob Member Posts: 297
    Pressure balanced

    What makes this high performance? Is each orifice pressure balanced for equal output? The pictures show a nice flame for sure.
  • Tim McElwain
    Tim McElwain Member Posts: 4,482
    There are no negative pressure

    gas valves that are what I would call multi stage in the real sense as the turn down ratios are defined by how low the firing rate can go based on burner design and port loading with the varying speed of the inducer. This falls under a standard which has not been changed here in the US, at least not to my knowledge. It has to do with the minimum firing rate for safe ignition based on using flame rectification as a flame proving system.
  • Eastman
    Eastman Member Posts: 927

    3400 btu minimum with 40 to 1 mod rate is excellent. combi boilers should make great use of this if the technology pans out.
  • clammy
    clammy Member Posts: 2,668
    nice upgrade burner

    just wondering if these burners could be used as a replacement for giaconni based boiler older munchkins /purefires .wondering how they would perform as compared to the mesh screen burners being some early mod cons used a stainless burner then upgraded to mesh but those early version where not as jeted as those blue jet are .just thinking out loud peace and good luck clammy
    R.A. Calmbacher L.L.C. HVAC
    NJ Master HVAC Lic.
    Mahwah, NJ
    Specializing in steam and hydronic heating