One-Pipe Steam System/Leaking Wet Return

taylorgeo

New to this forum. Not a professional, just an inquisitive homeowner.

New Burnham gas boiler installed one month ago. Was surging pretty bad at first. Plumber came back a couple of days later and added some green anti-surge additive. Surging stopped shortly after. Wet return is now leaking a month later.

I believe house was built in 1940. Probably original pipes.

What would cause a wet return to start leaking a month after a new boiler installation?

Thanks in advanced!

T

JUGHNE

taylorgeo said:

I believe house was built in 1940. Probably original pipes.

82 years of sitting with condensate water inside is a pretty good run.

Maybe the boiler treatment loosened up some sludge that was holding the water in the pipe....maybe.

But you are lucky to be able to see the leak. Is there any of it under the floor?

IIWM, I would replace all the piping below the water line. This is just the first leak.

You can replace it with type L copper, adding isolation valves above the water line at each end and hose fitting ball valves just under the isolation valves for future flushing.

taylorgeo

JUGHNE said:

Is there any of it under the floor?

Yes.

These are row houses with the garage under the house, and a door leading to the adjacent finished basement.

The leak is coming from under the ground right in front of the door on the garage side. I was thinking of burying the new pipe under the ground just in front of the door (around 30 inches), then run the rest of the return above ground straight back to the boiler.

There is a block wall at the back of the garage that is shared with the boiler room, so I'd have to drill a hole to feed the pipe through.

Sounds about right?

mattmia2

Btw the cure for the surging is to skim the boiler to get the oil from the new boiler and piping out of the system. Probably has to be done a couple times.

JUGHNE

This may have been leaking without being obvious for some time.
Was the old boiler taking on a lot of fresh water? And then was replaced because of hole in it?

So you can replace all of the return line...from where it drops down into the floor and all the way back to the boiler?

Whatever you bury, you do not want concrete in contact with it. I would get a high grade of rubber tube insulation, such as for AC lines, to protect the pipe.

Block walls are usually easy to pop a hole thru the hollow portion, from each side.

Did the steam installer add a skim port? Pictures?

EBEBRATT-Ed

@taylorgeo

Your plan to only bury the pipe under the door and run on top of the floor is a good plan

taylorgeo

JUGHNE said:

This may have been leaking without being obvious for some time.
Was the old boiler taking on a lot of fresh water? And then was replaced because of hole in it?

So you can replace all of the return line...from where it drops down into the floor and all the way back to the boiler?

Whatever you bury, you do not want concrete in contact with it. I would get a high grade of rubber tube insulation, such as for AC lines, to protect the pipe.

Block walls are usually easy to pop a hole thru the hollow portion, from each side.

Did the steam installer add a skim port? Pictures?

Gotcha. Yes, there was a hole in the old boiler and plumes of vapor coming out of the chimney.

Great point about the concrete. Will definitely pick up that rubber tube insulation. Skim port was added and boiler was skimmed.

Should I use copper or black pipe for the new wet return line? I live in the NE and was wondering if the new return line could possibly freeze or burst being that it's above ground in the garage.

Really don't want to run the new line through my finished basement – and the basement has no heat either!

JUGHNE

Depending how severe the garage might freeze, you could insulate the pipe for the full length.
If run along the floor, I would lay down a 2 x 4 for the pipe to lay on.
Then a 2 x 6 on edge for the front of the box and another 2 x 4 for a cap.
Secure the box to the inside wall. This would give an air tight channel and protect the insulation from damage.
Even add more insulation around the pipe, maybe 1" thick fiberglass.
Black pipe would handle a light freeze better than copper.

If the boiler is running the water will be moving.

taylorgeo

JUGHNE said:

Depending how severe the garage might freeze, you could insulate the pipe for the full length.
If run along the floor, I would lay down a 2 x 4 for the pipe to lay on.
Then a 2 x 6 on edge for the front of the box and another 2 x 4 for a cap.
Secure the box to the inside wall. This would give an air tight channel and protect the insulation from damage.
Even add more insulation around the pipe, maybe 1" thick fiberglass.
Black pipe would handle a light freeze better than copper.

If the boiler is running the water will be moving.

Okay, sounds good. Thanks so much for your help.

taylorgeo

JUGHNE said:

Black pipe would handle a light freeze better than copper.

Return line is going in tomorrow with black pipe. And your other suggestions. Thanks!