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Shutting down boiler for summer

sweetlou Member Posts: 22
I have an old boiler for steam heat. It was built in the 60's and I don't have a manual. What is the proper procedure when shutting it down for the summer. I was told to release a valve at least once a week during the winter . #1-Do I no longer have to do that not that its summer and I wont be using it? #2-Should the water in the boiler be drained completely? #3-Turn the pilot light off? Sorry if these are bad questions but I am new to this type of heating. Thanks


  • Summer Shutdown

    #1 - Yes, you still have to drain the low water cutoff (LWCO), but only once a month instead of once a week.

    #2 - No, leave the water in the boiler.

    #3 - Sure, turn off the pilot.
    8.33 lbs./gal. x 60 min./hr. x 20°ΔT = 10,000 BTU's/hour

    Two btu per sq ft for degree difference for a slab
  • sweetlou
    sweetlou Member Posts: 22
    Thanks - Another question

    Thanks for the reply. One other question....

    I was also told I need to drain the boiler once a month during the winter months (in addition to draining the low water cuttoff weekly). Is this necessary? Thanks
  • jpf321
    jpf321 Member Posts: 1,568
    drain no... bleed out dirty water yes ...

    As far as I know, it is not recommended to DRAIN the boiler completely... however, you should open the drain valves on the boiler every now and again to bleed out the dirty water that collects on the bottom. 
    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

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  • Brian_74
    Brian_74 Member Posts: 237
    I agree no drain

    My boiler is maybe a decade newer than yours and I'd be afraid to drain and refill it in the winter for fear of cracking it. I imagine that going from very hot water to very cold water would be quite the thermal shock to the old cast iron.
    1929 Ideal Heating vapor system.
  • Chris M_2
    Chris M_2 Member Posts: 67

    Thermal shock is an issue only if you fill the boiler without allowing it to cool first.  There's no problem draining the boiler and filling it again as long as you: 1. Shut it down first, and allow it to cool for an hour,  2. Drain it, and allow the "dry" iron it to cool for an hour. 3. Fill it, and boil it immediately to get rid of the corrosion-causing extra oxygen in the new water.
  • Brian_74
    Brian_74 Member Posts: 237
    And cut the pilot

    On boilers with constant on pilots, I think it would be safest to shut off the pilot, too. I would think that the cool down time would vary depending on ambiant temp, etc. So while an hour might be a good rule of thumb, in some cases it might take longer. My point was that it seems like a potentially risky operation do in the dead of winter with no notable gain.
    1929 Ideal Heating vapor system.
  • Johnny13
    Johnny13 Member Posts: 45

    This will sound really dumb, but do I turn off the pilot by turning off the gas supply? It lights itself.
  • Steamhead
    Steamhead Member Posts: 16,832
    If the pilot lights by itself

    every time the boiler starts, then it also shuts down when the boiler shuts down. So as long as the boiler isn't running, the pilot is off.

    This is called a "spark-to-pilot" system if the ignition for the pilot is a spark.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
  • Johnny13
    Johnny13 Member Posts: 45
    My pilot is still on.

    Tho my thermostat is all the way turned down. I know it is lighting itself because the gas has been turned off a couple times to have a meter replaced etc., and it came back by itself, which is something my hot water heater did not do. Is there something else that might need to be checked?
  • Brian_74
    Brian_74 Member Posts: 237
    Residual pressure?

    Is it possible that there was enough gas in the line that allowed the pilot to keep burning? A meter swap doesn't take very long. How do you know it's relighting itself? Did you see that it was off? How do you know yours isn't a constant on one? That's what I have, and I have to manually turn it off every year.
    1929 Ideal Heating vapor system.
  • Any way?,,,,

    you could post a few pics if the set-up you have?
  • Johnny13
    Johnny13 Member Posts: 45

    Turns out the problem was that I was an idiot. It was not lighting

    itself. I was looking in the wrong place. My situation is basically the same as Brian describes above. 
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