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End of Season?

AlexR Member Posts: 61
There's nothing in my boiler's manual (Burnham IN-5) about end of heating season procedure. Do you drain it or leave it as-is? It seems like flushing and an annual visit from a profession are better left until the fall. Suggestions?


  • Big-Al_2
    Big-Al_2 Member Posts: 263
    Good Question

    I don't know the answer either.  I've generally flushed out the boiler so any accumulated mud doesn't turn to rock in the off season.  Then refilled the boiler to the normal level, brought it to a boil, and shut it off until autumn.

    The local boiler guru tells me that after he cleans it up, he'll fill the boiler completely full, then fire it long enough to drive out the oxygen.  Having the boiler flooded supposedly prevents the formation of rust at the waterline. 

    I'm not an expert, though.  Do we have an expert who can comment on this?
  • toilburn
    toilburn Member Posts: 44

    Flooding the boiler for the summer is what they do to large commercial boilers
  • Chris M_2
    Chris M_2 Member Posts: 67
    Driving out Oxygen

    I've read a lot of comments about bringing the water to a boil anytime new water is added to the boiler, but I'm confused a little bit about this.  I'm no chemist, but If water is H2O (2 hydrogen/1oxygen), then how can there be room for "extra oxygen"? If the extra oxygen is not actually part of the water itself, wouldn't  it be a waste of time boiling the water when adding it, because new oxygen's going to get in there anyway through the radiator vents, and the existing void between the top of the water line and each of the radiators?  And alternatively, if we're talking about oxygen that's "part of the water", then wouldn't that water cease to be water if we boiled it to remove oxygen?  I thought that boiling water turns to steam, but that steam is still exactly the same, chemically speaking, as the water it came from.  I hope I'm not sounding like a nitpicker... I just want to understand the chemistry a little better here.  CMannering
  • Brian_74
    Brian_74 Member Posts: 237
    Dissolved Oxygen

    Drinking water (as well as fresh water in ponds and lakes) is more than H20. Among other things, there is dissolved oxygen (i.e., tiny oxygen bubbles in the water). The ability of water to hold dissolved oxygen is inversely related to its temperature. So when you fire up your boiler, you're raising the temperature of the water, which forces it to give up some of the dissolved oxygen.
    1929 Ideal Heating vapor system.
  • Jeremy_16
    Jeremy_16 Member Posts: 113
    Flooding Boiler in the Summer

    What are the pros and cons to flooding a large commercial boiler in the summer? I know some people that recommend this and others that have never tried it and are wary of doing it. What do boiler manufacturers recommend?
  • malp
    malp Member Posts: 27
    bryant recommends

    The manual for my residential boiler recommends filling the boiler with water during the summer. The manufacturer is Bryant.
  • Summer Shutdown

    At the end of season I have a burner guy clean and adjust my burner. I used to do this in the fall but found it was easier to get someone out in the spring when it wasn't such a rush. (Since they aren't as rushed I also think they do a more thorough job) Next I drain and flush my system. I then add new water and bring it to a boil and add Rhomar 903

     As for flooding the boiler -  I used to have to do this to cover the domestic HW coil if I was going use the boiler for HW during the summer. I found it more practical to switch over to an electric water tank and shut the boiler down.  In the fall I just give it a quick flush and change water.

    - Rod
  • FJL
    FJL Member Posts: 354
    edited March 2010
    Funny ...

    My contractor said nothing to me about end of season/pre season maintenance after our new boiler was installed in the summer of 2007.  Odd if only b/c I'd think he'd not miss an oppty to secure some additional work for himself.  So I don't really know what is expected to be done.

    What is recommended?  I understand what people on this board do, such as Rod above, which may be more than what is recommended.  So I'm curious about that.  Right now, I'm ashamed to admit that we don't really do anything except turn it off at the end of the season and then turn it on at the start.

    I had built into my contract that the contractor come out to perform pre-season maintenance after the first full season in which the boiler operated, but I have to say I don't really know what they did and didn't know enough what to ask to be done to keep the boiler in tip top shape.
  • jpf321
    jpf321 Member Posts: 1,567
    the proof is in the ice ....

    take an ice-cube tray and fill half of it with tap water and half of it with tap water which you boiled once .. you may also want to fill part with some clean-ish boiler water ...

    then put in freezer and freeze .. you should find that the boiled-once ice cubes are crystal clear and that the straight-from-tap ice cubes are cloudy .. i don't know what you'll find with the boiler water .. i guess I should test this myself.
    1-pipe Homeowner - Queens, NYC

    NEW: SlantFin Intrepid TR-30 + Tankless + Riello 40-F5 @ 0.85gph | OLD: Fitzgibbons 402 boiler + Beckett "SR" Oil Gun @ 1.75gph

    installed: 0-20oz/si gauge | vaporstat | hour-meter | gortons on all rads | 1pc G#2 + 1pc G#1 on each of 2 mains

    Connected EDR load: 371 sf venting load: 2.95cfm vent capacity: 4.62cfm
    my NEW system pics | my OLD system pics
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