Riser Leak Noticed-Any guesses as to what we'll find?

cubicacres

After firing up the boiler a few weeks ago for the season, we just noticed some water on the basement floor and saw it was coming from the last riser to the 1st & 2nd floor tennant bedroom radiators as shown in the photos (then one more 1st floor hall radiator/riser after that, then it returns via the ceiling dry return back to the boiler room & drops to the boiler). We'll take off the insulation and look up the riser to see if we can isolate the leak area (and go into both bedrooms to see if it's near the radiator valves or the pipe run itself that's leaking-with any luck this might be a big portion of the higher water use we noticed the past season). Any thoughts on what it might be/stopping the leak & letting the insulation dry out & replacing it in a few days/weeks, or does fiberglass insulation lose effectiveness long-term after being wet for a while & should be replaced with new insulation?

ChrisJ

Wet fiberglass

Jamie Hall

Fiberglass insulation can be dried out... eventually... but if it's been at all compressed while wet, it never really recovers. Better to bite the bullet and replace it. As for finding the leak... assuming that this is meant to be a dry return (not standing water like a wet return), the most likely places are the threads of fittings. Particularly any where the pipe turns from vertical to horizontal, or vice versa. Always assuming that you don't get lucky and find a leaking valve...

Larry Weingarten

Hi, When looking for the leak, I'd start at the highest possible point and work your way down. It MIGHT be less work that way.

Yours, Larry

JUGHNE

When I could not find an elusive water leak and narrow down which fitting it was, I would tie cotton rag around under what could be suspicious. About 1/3 of a dish towel size.
That would be each riser coming up thru the floor etc.
These things don't leak if you are watching them.

The cotton rag stores the evidence for hours.

cubicacres

Thanks, we added some rags to narrow down which fittings & pipe sections/elbows near the ceiling in the basement it might be leaking from & will check for dampness periodically. The 1st floor tennant agreed to put some paper towel under his floor estuchion plate on the riser to verify if it's the radiator valve or below his floor causing the leaking. Glad to learn the riser just went a few feet up to a single radiator on the 1st floor without feeding another radiator on the 2nd floor, so we've narrowed it down to minimal inside-wall cavity pipe replacement issues we were concerned with originally

cubicacres

We think we found our culprit, a 1-2 drips per second leak near the bottom of this radiator valve. It was the hairline crack running about halfway around the base beneath the 1 in this photo. We replaced the valve with a spare on hand. This valve was new & replaced by us about 2-3 years ago-any guesses as to how the crack developed? We did use pipe dope both times, although I think that isn't reccomended (the technician insisted, so we deffered to him this time)

ethicalpaul

I would guess that someone used too big a wrench or too big a muscle on the valve and sunk the threads so deep that they caused the valve to crack, or it was a manufacturing defect, or both.

It wasn't the pipe dope's fault but I use just tape.

Jamie Hall

I'm going to go with casting defect. Unless the plumber was a real gorilla... and took one turn too many.

cubicacres

Thanks, glad we had a spare valve on hand. We left the last part in the radiator since our spare was the same model that was installed a few years ago, so we're hoping we saved some time not needing the spud wrench & it will work ok. If not, would leaks tend to develop around the union between the radiator & valve we just installed? Related to that, I see 3-4 unions we didn't use a few years ago with the same short-cut of not replacing the nipple inside the radiator with the new valve. Is there any use for those nipples now that the related valve has already been installed on those radiators & doesn't seem to be leaking?

Jamie Hall

If the valves are all the same make and model as the one you had before, the union should be OK. They do tend to vary between manufacturers -- but not within. They aren't custom lapped!

STEAM DOCTOR

Is radiator properly supported? Using the valve to support the radiator,  can lead to cracks. More likely in front portion of valve area of union threads. 

cubicacres

Previously, we had some shims to pitch the radiator gently toward the supply valve for condensate return help, but we'll check it out since the tech was yelling at it & didn't seem to care about the level of the radiator today. He also said some things that made us realize he wasn't the steam expert we specifically asked the company for due to our steam boiler needs. He also left our forced air furnace plastic drain box off inside the furnace after the tune-up, leading to a gallon of water on the floor this afternoon. Called the after hours number & was told we would be billed for a service call even though they have a 30 day labor warranty written on our paid invoice from this morning. That's $600 for cleaning the boiler burners, swapping our radiator valve & a forced air furnace tune-up & replacement humidifer fan & manual control we wish we had back