Loss of water in one pipe steam boiler setup

Spunky424

So I finally got my system balanced well that the second and first floors heat pretty evenly with venting the mains quickly and sizing the vents on the rads properly as well. My boiler is still oversized by 20% via my EDR calculations but nothing much I can do about that until I get a boiler service guy to come and down fire the boiler with a smaller nozzle.

Now on to the real problem. It's 15 degrees outside and my boiler is firing pretty frequently but only when it's suppose to via the stat. Last night I checked the water levels on the boiler via the site glass and all was well. Today the boiler was cutting out due to low water via the lwco. Where the hell did all my water go? There was only about 2-3" of water in the site glass when I realized the lwco was kicking in. I immediately filled her back up to the appropriately level but I'm worried about where all the steam condensate went?! How do I go about troubleshooting this?

Fred

Was the boiler running when you saw the 2-3" of water in it? If so, you need to check it with the boiler off, allowing at least 15 minutes for the condensate to return to the boiler.
Is this a 1 pipe system?
Can you determine if any of the wet returns might be clogged, not allowing the condensate to return to the boiler?
Has any work been done on the boiler or piping that may cause the boiler to need skimming? Many times if there is oil on the surface of the water, in the boiler, the water will be pushed up into the risers, possibly the header and back into the wet returns but it should return quickly if you shut the boiler down.
If it is an actual leak, that much water should be obvious.
How old is the boiler? Any chance there is rust through in the top of it letting steam escape out the chimney?
Any gurgling in any pipes or radiators?

Spunky424

The boiler was cutting in and out due to the lwco. I noticed it short cycling and decided to give the site glass a look. It was low on water

Yes this is a one pipe system

How would I go about checking the wet returns and if they are clogged?

I recently added two used radiators to the system. Replacing one and adding a new one to an existing capped off pipe.

The boiler is about 3-4 years old. It is a Weil McClain sg04

No gurgling in the pipes that I noticed.

Fred

Are the wet returns above the floor or buried under the basement floor? Are there any drain spigots or plugs on the boiler end of any of them?
Has the boiler lost anymore water since you last filled it? If the returns are clogged, you should soon start to get some hammer towards the end of the Main that drops to the wet returns. If that is the problem, you'll know soon enough.
If the wet returns are buried, there is a reasonable possibility one of them is leaking under the floor where you can't see it.

What about the boiler water? Is there a lot of bounce in the sight glass? Have you shut the boiler down long enough to see if it overfills? if so, you need to skim it.
Is your pressure down as low as you can get it, under 1.5PSI? If it runs too high, it could keep condensate from being able to return to the boiler. Have any of the rads stopped heating, or any other indications they are holding water?

Spunky424

Fred said:

Are the wet returns above the floor or buried under the basement floor? Are there any drain spigots or plugs on the boiler end of any of them?
Has the boiler lost anymore water since you last filled it? If the returns are clogged, you should soon start to get some hammer towards the end of the Main that drops to the wet returns. If that is the problem, you'll know soon enough.
If the wet returns are buried, there is a reasonable possibility one of them is leaking under the floor where you can't see it.

What about the boiler water? Is there a lot of bounce in the sight glass? Have you shut the boiler down long enough to see if it overfills? if so, you need to skim it.
Is your pressure down as low as you can get it, under 1.5PSI? If it runs too high, it could keep condensate from being able to return to the boiler. Have any of the rads stopped heating, or any other indications they are holding water?

Wet returns are all above the floor. See pictures attached. No drain spigots or plugs in the wet returns

If say the water in the site glass moves about 1/4" up and down when the boiler is on. When the boiler is off Overnight it does not overfill

My pressure is set to 0.5 cut in with a differential of 1.5. And all rads get hot and are heating as they should

Fred

Does it continue to lose water? There has to be a leak somewhere or that water is in the return and can't get back to the boiler.

Spunky424

After the fill up two nights ago there has not been any missing water. Keeping a close eye on it every few hours. Will report back if something else is found.

Spunky424

Had to fill about an inch of water in the site glass up since it was below the fill line again. I've got to find where all this water is going. I'm getting pretty worried

Fred

How much water does that boiler hold? An inch in the sight glass, is that a gallon? Half Gallon? More? Do you see any steam clouds coming out of your chimney when it is running, indicating water steaming away through a hole/crack in the top of the boiler? When you look in the burner compartment, do you see any indications of water/rust/moisture/ mineral residue left behind from steaming?

Captain Who

FWIW, for my Peerless 63-04L with a 10.8 gal rating to NWL, I have found that 3.27 qts = 1 in. on the sight glass.

I've been adding maybe 1/8 in. or more every day or two, but it has been pretty cold lately.

Spunky424

Captain Who said:

FWIW, for my Peerless 63-04L with a 10.8 gal rating to NWL, I have found that 3.27 qts = 1 in. on the sight glass.

I've been adding maybe 1/8 in. or more every day or two, but it has been pretty cold lately.

Is that normal? Or a sign of a dying boiler?

Jamie Hall

Adding 1/8 inch every day or so is... perhaps a little high (a gallon or so a week) but not totally out of line, so far as the boiler is concerned. Slightly fanatic so far as the operator is concerned!

For reference, some systems take a lot less -- the building I super takes about 2 gallons per year, exclusive of LWCO blowdowns.

Captain Who

I think it is normal. I have a pretty severe night time setback of 8 deg F and it has been below zero lately with the wind chill factor. That works the system pretty hard. There will always be some water lost through the vents unfortunately. I did notice yesterday morning when it was recovering from setback that my Gorton #1 main vent (I know it is too small) was not holding the steam back completely when it was cycling on the pressuretrol so it may need replacement. I already cleaned it with vinegar so I did everything I could do.

I assume you have checked all your radiator and main vents with a mirror to make sure that they are not leaking any steam when they are hot?

Fred

There will be some evaporation, especially on really cold days like we've had these past 2 or 3 days but you are using almost a gallon in a day. Not that much evaporation. Water is going somewhere. If it is the boiler, find it. Most of those boilers have a 10 year warranty on the boiler block. Do you see any steam out of the top of the Chimney?

Captain Who

Jamie Hall said:

Adding 1/8 inch every day or so is... perhaps a little high (a gallon or so a week) but not totally out of line, so far as the boiler is concerned. Slightly fanatic so far as the operator is concerned!

For reference, some systems take a lot less -- the building I super takes about 2 gallons per year, exclusive of LWCO blowdowns.

Ha ha yeah I'm being fanatical a bit I guess. What I'm doing is trying to cope with a Hartford Loop that was installed incorrectly where the top of the close nipple is only 1/8 in. below the NWL (instead of 2 to 4 in. as specified by Peerless) ! I used to maintain the water about an inch or more above the NWL but this year I'm trying to maiximize the steamchest by keeping it only about 1/4 to 1/2" above, to try to keep the steam dry. I also have incorrect near boiler piping so it is harder to keep steam dry. That is requiring me to watch the waterline like a hawk.......a real pia. If the waterline goes below the Hartford, the first radiator on the main lets me know by making clanging noises and boiling sounds. That's always the signal to add a little water.

RomanGK_26986764589

For a reference, I add about 7-8 gallons of make up water per season.

Dave0176

I don't know if this is the issue or the cause but it probably isn't helping, but the boiler is not piped right. There is no header and the riser size is a bit small.