marson wrote:

So here's the deal. I am building a new house which is basically
done, sheetrocked, finish floors, etc. The only problem is that we
can't get a plumbing final passed--seems like there is a fitting that
has come apart in the vent portion of the DWV. I am looking for some
brilliant ideas to find it, short of filling the system with water and
looking for the leak.. We have tried the "peppermint test" --dumping
peppermint down the vent, follwed by hot water, and can't smell
peppermint anywhere. We also tried a camera, but were unable to fish
it in the lines smaller than 3".

A few ideas I've had are--

1) devising a hillbilly smoke test--setting a shop vac to blow. Put a
little water in the tank, and add dry ice, and hook this up to pump
"smoke" into the system.

2) Hiring a guy with an infrared camera. Attach a heat gun to the
system. Pump heat and look for heat.

Anyone have any other ideas?


Pressurize with compressed air. ~20 psi. That requires tight
sealing of all openings. Listen for telltale whistle.
Or, as suggested, use a pro listening mic for even ultrasonic signals.

You could introduce faux smoke from a smoke generator or
"smoke" candles if it's likely you could see the smoke where
it exits. Or introduce mercaptan odorant (used in natural gas).

Jim