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water level in boiler and auto-feeder

nt101nt101 Posts: 3Member
edited March 10 in Strictly Steam
I recently posted and found the forum exceptionally helpful so decided to post again. Thank you everyone for your help and responses! We recently moved into a two-family building with two Burnham steam-fired boilers in the basement. Each apartment/unit is about 1,000 square feet. We live in the bottom unit and our monthly winter bill has been about a couple hundred dollars, but the upstairs unit has been nearly twice that. The building is not insulated (although the attic is), but I would imagine that should impact both of us relatively equally. I took a look at the upstairs' unit boiler, and the water level was below the bottom level of the look-through glass (see image below) while it was running; as in, I couldn't see any water in it (in our boiler, I can always see water in the glass, even when it's running). As soon as the boiler turned off, the water level rose a bit, I would say two inches from the bottom (see second image). I also noticed the auto-feeder light is not on, while the low-water cut-off light one is on, so I'm not sure if the auto-feeder is not working (see third image).

I was wondering if the forum could help us with a couple questions:

1. What is the appropriate amount of water that should be in the system while it is running? Should I be able to see it in the glass while it's on?

2. How do I know if the auto-feeder is working or not? Should I press the "reset" button?

3. What might be other causes of this significant difference in heating costs between the two units that I should investigate?

Thank you!


  • FredFred Posts: 7,814Member
    The water level, when the boiler is not running should be about 2/3's up the glass. During a heat cycle, it may drop to about 1/2 the way up the glass. Judging from the look of those sight glasses, it looks like those boilers haven't been serviced in quite a while. They need to be cleaned, maybe skimmed and all of the safeties checked and repaired/replaced. There is no way the water level should drop below the sight glass and the LWCO not shut the boiler down or the auto water fill not add water. That is a very unsafe operation. Get them fixed ASAP.

    As for the difference in utility bills, you are benefiting, to some degree from the fact that your neighbor's apt buffers you from some external temp and wind. They heat their apt with all sides and the top exposed to the cold. You heat yours exposed to the sides but not the top. I might add, you don't mention if both apts are maintained at the same temp. Thermostat settings are a big factor in fuel consumption.
  • neilcneilc Posts: 659Member
    gage in 2nd picture looks to be up around the 5 mark,
    what are your pressuretrols set at?
    have their pigtails been checked and cleaned lately?
    guessing based on the dirty sight glass pictures that you're behind on this maintenance,
    and high pressures are pushing water out of the boilers,
    dirty water could also be perculating up into the system as wet steam,
    pictures of the boiler piping above the boiler to the ceiling?
  • neilcneilc Posts: 659Member
    I recant my gage at 5 statement
  • Jamie HallJamie Hall Posts: 10,282Member
    Doubling down here on @Fred 's comment: if the water level drops below the sight glass, the boiler should be shut off by the low water cut off. No ifs, ands, or buts. Any other reaction by the boiler and its controls is very dangerous.

    So... it would appear that the autofeeder on that boiler isn't working (might it just be shut off at a valve), nor is the low water cut off. At best, perhaps they just need maintenance. Next up, they may need replacement. Worst, someone may have bypassed them as a "nuisance".

    That boiler should be turned off and left off until it can be demonstrated -- by actual trial -- that the low water cut off will shut off the boiler before the water level drops to the bottom of the sight glass.

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,631Member
    yup @nt101

    As @Jamie Hall & @Fred mentioned you need to get this serviced. You don't want to pay for a boiler replacement
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