Cold radiator that shifts from one room to an adjacent room

James E. Cassady

I have recently bought a house made in 1924 that has a 10-15 year old one pipe gas water boiler heating system with iron piping that looks older than that. I have a problem with the upper bedroom's radiator staying cold during house heating. This has been going on for 2-3 months. Also, the problem shifted recently to an adjacent room which previously was heating up it's radiator fine. Now the previously cold room has a warm radiator and the adjacent room's radiator is staying cold. They are both on the 2nd. floor of a one pipe boiler system. I have noticed that a 3 ft. section of the basement floor return pipe just behind the boiler is corroded, rusty, and is seeping moisture onto the floor. It is not a dripping leak, but just is a wet moisture spot on the concrete below the corroded pipe. It looks like it has been rusting there for a long period of time. Also, it is hard to control the level of the water in the boiler tank. So, it has been left overfull most of the time to guard against running the tank out of water. Lastly, when heating the system, the pipes tend to make a knocking sound from the basement. How can I fix my system to where this upper room's radiator gets warm when it's supposed to ? Should I replace the section of pipe that is seeping moisture onto the floor and how can I keep the proper water level in the boiler tank ? Jim C.

will smith_4

Jim-

By what you've posted, it seems like you have classic symptoms of a plugged up wet return-and that could be what's causing heat distribution problems. As the boiler cycles, steam leaves the boiler, zooming out to your radiators. Once they heat up, your vents close, then as the steam condenses, it's supposed to work it's way back to the boiler. If it doesn't get there fast enough, the low water control will add water. Eventually, unless you have a major leak somewhere, the condensate does get back, raising the water level even higher. You end up with a very inefficient steam boiler, as the distance between the water line and the lowest steam carrying pipe keeps getting lower and lower. Check out the wet return-replace it if it's plugged. Good Luck!