Water loss

sasacook

I have a one pipe steam system. Burner was replaced about 6-7 yrs ago. No problems until recently. I have add water to the system daily for the past few weeks. The LWCO keeps firing due to the low water levels as it burns off the water overnight. I've already replaced all the radiator air vents, which may have helped a little but certainly hasn't corrected the problem. I see no water around any off the radiators, the boiler, or along any of the returns. Is it possible that the boiler has an internal leak and the water is evaporating before it's able to collect on the ground? Any other thoughts?

Jamie Hall

Look at your chimney when the boiler is firing. If you see just a wispy sort of cloud, that's OK. If you see a billowing steam cloud, that's not OK. My bet is that you are going to see the latter, and you have an internal leak at or just above the water line into the firebox.

nicholas bonham-carter

The definitive test for this is to overfill the boiler to the mains, when cooled off somewhat, and watch for leaks in the firebox area, for a few hours.
If the boiler must be replaced, then you must add up the EDR of the radiators, in order to select the proper size of the replacement.
Post some pictures of the boiler piping for more advice.--NBC

BobC

Are there any returns that go under the cellar floor or in places you can't see?

Bob

sasacook

@Jamie Hall
I have a power vented unit, doubt that matters but I checked the vent several times...no clouds of billowing white steam. In fact, could barely see any moisture, but I'll check again as it gets dark out, maybe it'll be easier to see?...

sasacook

@nicholas bonham-carter
Here is a pic of the boiler and near piping. Not sure if this what you were looking for?
I'll try the overfill and check for leaks and get back to you...

sasacook

@BobC
I have risers in the walls that aren't fully visible but I wouldn't figure those to be a problem. All the basement returns are visible. No obvious water under them.

sasacook

@nicholas bonham-carter
Near boiler pipes

sasacook

@nicholas bonham-carter
So I "overfilled" the boiler and sure enough...water dripping out the bottom! There's no repair for that, is there? The whole unit needs to be replaced?

Fred

If you can take a cover off of the boiler, take a look at where the leak is. If you are lucky, it may be at /in the riser pipe out of the boiler. If it is in the block, a boiler replacement is probably the only solution and you need to have the water quality tested so the next boiler doesn't meet the same fate. How old is this boiler?

sasacook

10 years old. I know our town has historically very hard water. About 4 yrs ago I had a water softener installed in the house

sasacook

@Fred
What should I be looking for, or not looking for in our water?

Fred

sasacook said:

@Fred

What should I be looking for, or not looking for in our water?

The chloride level has been a noted issue with Burnham boilers for years. It is a problem with all cast iron boilers but Burnham seems to be especially sensitive. I believe Burnham even published a Tech Bulletin on the issue a few years ago. When/if you have the water tested, make note of a high cloride level, well above Burnham's recommendations.
Also, do you store water softener salts or other chemicals near the boiler? They can affect the rate of corrosion as well. What model boiler is that Burnham? They also had serious issues with the quality of the castings on the V7 series boiler.

sasacook

@Fred
Here's the plate on my boiler...
I'll look into the chloride, thanks
No salt tablets near the boiler

Fred

Have the water tested, look for high chlorides. Post any results that are noted as outside normal levels. Someone can tell you how to adjust for those variances.

Jamie Hall

Also excessively soft water is not kind to boilers. It is surprisingly corrosive...