Detecting a steam leak

Jeff_44

I am losing about 1/2 of water in the sight glass per every two weeks. I think I have a leak somewhere in the system. I'm pretty sure the boiler is not leaking (I've overfilled it and let it sit and had no water on the floor - and there is no white plum coming from the chimney).



Any thoughts about how to trouble shoot a system leak?





Thanks (as always)

Jamie Hall

One pipe or two?

If it's one pipe, check all the radiator vents -- it's surprising how much steam can wander off through a vent which isn't closing.  And it won't help the wallpaper or finish in the room eitther, given time...



Might also be a leaking packing on a radiator valve -- either one or two pipe.



Otherwise, check the main vents; perhaps one or more of them isn't closing properly.



Also -- wet returns have been known to leak.



Other than that... a steam leak can be a bear to find, as you won't see it.  Might be able to hear it.  Maybe...

Jeff_44

One Pipe

Thanks, I have a one pipe system. I just replaced all the rad vents in the fall with Maid-o-mist. I do find that there is some water in them. I have checked for leaks in the wet return and found non. I've tightened all the rad valves and their respective nuts. My boiler doesn't generated much pressure and I have a 0 - 3 lbs gauge. When the boiler is burning, the gauge needle bounces but never gets much past the zero. There is one rad vent that whistles a little once the boiler cycles off - don't know if this means anything?