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4Barrel Member Posts: 125
woke up this morning to a cold house and found my boiler had been cycling on/off on pressure limit. the sight glass showed very dirty water, the color of coffee, and surging up and down like mad. i pushed up the pressure a few ozs, up to 14, and the system runs.

i had added a new radiator and runout two days ago, and the slight glass had showed some signs of oil residue from the install, but was generally clear, and all ran nicely until this morning. I was planing a skim at some point, once we get some higher temps.

any thought son why my boiler suddenly got all dirty, and how should i blow out the dirty water? i don't think a skim will be enough, and i don't have kings valves...


  • jpf321
    jpf321 Member Posts: 1,568

    do you have an auto-feed? perhaps the dirt is being introduced by the feedwater rather than your system .. i know sometimes if the Water utilities are doing work or a main breaks or something, we could see dirty domestic water supply from the street.

    was the rad you added a factory-new rad or had it once been installed before? perhaps a factory-new rad needs a few days to rust up properly

    just a couple of thoughts
    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
  • Steamhead
    Steamhead Member Posts: 16,714
    First thing to do

    is to drain out as much of the dirt as you can while the boiler is still warm. Then when the boiler is cool (NEVER when it's hot) refill the boiler, let it run for a while and drain it again. Then skim it and see how it does.

    I repeat, NEVER add cold water to a hot boiler. Ever. You'll probably crack it.

    What probably happened is you loosened a bunch of dirt when you hooked up that radiator, and it worked its way back.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • 4Barrel
    4Barrel Member Posts: 125
    got it

    thanks steamhead. i was thinking of draining after i get the place a warm again b/c i figured i would need to wait some time before re-filling again. so, just do a bottom blowdown? how long until it's safe to re-fill? (understand to repeat process and skim if necessary)
  • 4Barrel
    4Barrel Member Posts: 125
    yes, i have autofeed

    i had not thought of dirty supply, but then all my water would be dirty, wouldn't it? it's not a new rad, but i did brush out some old crud from the bottom and got it pretty cleaned up b4 install...
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