Pinhole leaks in old steam boiler return.. clog? How to unblock?

LegendsCreek

I have an old Peerless steam boiler in my house with 2 zones. The return has pipes going to a big pump beside the boiler (I think it's supposed to take all the return water and put it back in the boiler).

When I bought the house 3 years ago the 2" iron return line developed a single pinhole leak which I patched with a pipe clamp. Last year another hole developed beside that one, which I patched with a second pipe clamp. Last week a third hole developed about 40 feet away in a soffit above a bathroom ceiling.

Oil company came out and will not touch the pipe until spring, but while he was at my property I asked him to open up the pipes next to the return pump, and to remove one of my patches, so we can determine where the standing water was. He removed one of my patches and steady stream of water came out. He removed a vent beside the pump, stuck his finger in and it was dry and gummy. No water came down at all, which tells me there is some sort of clog after the pinhole I patched.

Since my oil company won't touch anything until spring, I was thinking I might be able to unclog the clog somehow so that I don't keep standing water inside this return, creating further holes. In the spring they said they will cut out the leaking pipe and union in a new one.

I have a car tire, with a vibratory motor attached to it, and I use it to vibrate concrete in forms to make planters. I was thinking I could put the tire onto the pipe where I think it's clogged, and unclog it. Would this be a waste of time? I feel like I need to do something because these pinholes are only going to get worse.

Oil company said it will cost 80 grand to put in a domestic hot water system, pull out all the steam radiators and replace them all with panels. I don't want to spend that!

Jamie Hall

You don't want to pull out the steam. You want to fix it. Which should be very simple.

On the leaky pipe. If you have one pinhole leak, there are others just waiting to happen. As you have found. Further, they are probably not happening because they are gunked up, so cleaning the pipe is only going to make the leaks worse.

Vibrating the pipe will surely make it worse, and may cause it to break entirely.

Replace the pipe. Replace, in fact, the whole length of the pipe.

Now that tank and pump. I doubt you need them, but some pictures in the vicinity of the boiler and a more complete description would help... there are a few situations (rare, in a house) where they are needed.

LegendsCreek

Thanks for the info Jamie. I keep hearing from the oil company that we should replace it because finding techs to work on these are becoming rarer and rarer these days.  Anyway, Regarding the return pipe, there is something causing the water to back up and come out the pinholes. I was just looking for a say to unblock it. There is a clean out before the holes. Could I snake something in there instead?

Here's a photo of the boiler and pump. 

Jamie Hall

Where are you located? We may know someone in your area who actually knows steam well.

On the plug. You could, if you can get at both ends of the offending pipe, try just running a snake up it from the lower (plugged) end to get things moving a bit better, and then running water from a hose down it to flush things out. There is a risk even then of making a leak worse, but it's worth a try.

Looking at your picture, I'm thinking that it would be possible to repipe much of the wet return system so that the tank and pump weren't needed at all -- but I'd have to go over the whole system to be sure. A good steam man would know. It would also reduce the trip hazard from that pipe coming towards the camera...

LegendsCreek

I am in Londonderry, Vermont. I looked at replacing the boiler itself with a newer steam boiler this past summer, and my own oil company refused the job. Nobody wants to work on steam here, and nobody returns calls, unfortunately.

Jamie Hall

You might give @Charlie from wmass a PM. I know he works in Vermont from time to time, and he is one of the best. Just clck on the name and a window will come up so you can send him a message.

Charlie from wmass

Are you sure the pump is working? When you say 2 zones how are they controlled?

LegendsCreek

Charlie from wmass said:

Are you sure the pump is working? When you say 2 zones how are they controlled?

Hi Charlie, thanks for chiming in. Yes, the pump is working. I hear it turn on and kick water back into the boiler. Both zones are controlled by an electronic zone valve inside the 2 supply pipes, attached to thermostats. When the zone calls for heat, the electronics open the valves.