Broken Water Pipe - Need Columbo

[Woodboy]

Help me with some detective work. In my mountain cabin when my son turned on the water at the inside main, he noticed water dripping out of a ceiling heater vent (dry walled ceiling of a basement). Interior temp was 50 degrees which is where the forced air furnace thermostat is set – too warm to freeze and we’ve never had a problem in this very tight cabin. Above this part of the basement is the kitchen (sink, dishwasher and tap for the ice maker). I know where the water starts (water heater), but the majority is buried in the ceiling. The problem is how to isolate the general area of the break without woodpeckering the entire basement ceiling. Since the furnace vent might just be at a low point, I can’t rely solely on using the first drip point as an indicator.

Headed up this weekend with a dry wall saw, copper pipe, fittings and a torch – any suggestions?

[JSCOOK]

FWIW,
Be sure to check the sink's drain closely ... I have seen several sink drains leak water after a number of years, especially if the trap has a clean-out plug at the bottom of the U shape section ... poor gluing, loose compression fittings, forgotten glue in joints, rotting steel drains ... DAMHIK

[Stytooner]

If it was plumbed well, you will have valves to the dishwasher and the ice maker. If you do, then you can turn these off to test. If not, then I would start by initially looking under the sink at the supply lines and then to each of these appliances. Don't forget high behind the sink at the faucet connections.
If pressure has been off the lines for awhile, the connections can leak some when pressured up. Especially those crazy ice maker fittings.

If it was a line break, there would be no doubt about it and it would reveal its location pretty quickly.

[Deadhead]

I'm certainly no expert and have only limited experience with plumbing leaks. But that limited experience was with my dad's first floor ceiling. His think copper pipe had been developing pinhole leaks for a while before there was any indication on the ceiling drywall. After about the 3rd time of having "the" leak fixed and drywall patched only to have another leak a few months later, he decided it was time to cut into the drywall for a thorough inspection. There were dozens of leaks that just hadn't stained the drywall yet. That's when we decided to cut out all the pipe and install new (btw, we used CPVC because of our amateur status as plumbers).

My advice is if you're cutting into the drywall anyway, go ahead and cut a large enough section on a long horizontal run to be able to inspect the pipe. You're looking for green stains on the outside of the pipe.

[jseklund]

I'm no plumber, but here is what I've found.

First- don't assume the leak is in the pipe. JSCook's advice is very good- check the drains. Another trick I have used it to get a bucket, put it in the sink, and have someone watch the leak while I fill the bucket. If it is leaking then- it is probably the water running up to the sink. If it is not, then dump the bucket down the sink and see if tha does it. Not the most elegant solution, but for a non-plumber, it has worked for me to help determine that the problem was a drain.

The next step would be to shut off all the water at the sink, dishwasher, etc.- if possible. If it is still leaking at this point, I would say it is the water leading up to the appliances, and not in the water coming down.

If it is the water leading up, you will have to open the ceiling I would bet. However, double check the pipes in the cabinets, and anywhere you can get to. For instance- the pipes under the sink may have a leak that you can get to, but you haven't noticed because it is just trickling down the pipe, back into the ceiling below, and building up in the drywall- until it starts beading and dripping. In other words, look for the easiest way out first, and then go the more difficult route once you've eliminated that possibility.

If you do open the drywall and find a lot of green pipes, you may want to replace and/or put on a filter system. The green is some kind of efflorescence (sp?) that is caused by chemicals in the water corroding the pipes, I believe. Filters often help with this.

Good luck, hope this helps!

[scorrpio]

If the water is dripping out of a vent, you'll likely need to replace some of it near the vent anyway. Cut a hole right where you observe the drip, and either poke your head in there, or use a mirror. Have someone turn water on a little bit - you should be able to see where the water enters the joist bay.

[Deadhead]

Cut a hole right where you observe the drip, and either poke your head in there, or use a mirror.

Digital cameras work great for something like that too.

[eezlock]

leaking plumbing....

I would be closely checking those supply lines to the dishwasher
and possible plastic line to icemaker. I truly hate that plastic junk for icemaker supply lines, copper is better, can be tightened down for less
chance of leaking and if fridge gets moved around and back to it's original
place in kitchen with plastic tubing connected to icemaker...watch out
you'll kink or pinch that line everytime and start a leak! Also, check
supply valve to icemaker, if it is the saddlevalve type, and is leaking
replace it with type that uses a soldered in connection and compression fittings...they will last almost forever! eezlock