Leak Test on DWV changes

[Jim Bannon]

I am moving drains for tub, toilet, and lav, and adding a new shower drain as part of a master bath remodel.

I was planning on just extending the drains to their new locations — with proper vents and slopes.

The inspector says I’ll need to have a leak test done using a 10ft head of water. My dillemna is how best to plug the drain pipes over in the old ABS piping where I was hoping not to have to disturb anything.

I’ve identified one way to do this that would allow me to avoid breaking into those pipes. I could use inflatable test plugs with extension hoses with the whole thing shoved 4ft down through my new drain stub-outs. But the water would be on the “wrong” side of the plug, so I would need to inflate the plugs and then close the hose up inside the pipe with the water and then put a cap on my stub-outs. After the test, I’d have to create a vacuum in the vent pipe with another plug so I don’t have water gushing all over the floor while I remove the caps on the stub-outs to deflate the plugs in the drain lines.

Sounds complicated, but it would theoretically allow me to avoid cutting into the existing drain lines.

The more conventional (I think) approach would have me cutting out sections of the old drain, inserting test tees, and using the Mission “Tee-Seals”. After the test, remove the inflatable Tee-Seals and replace with regular threaded ABS plugs. Is that allowed in a ceiling that will be closed up ?

I’m worried about what might happen in the first approach since I have no way to secure the cable on the inflatable plugs. If they slip, they could move beyond reach and I won’t be able to retrieve them. I don’t know how likely that is, but if it happens, I could be in big trouble.

Should I just bite the bullet, remove more ceiling and break into the drain lines and use the more conventional method ?

[SylvanLMPParticipant]

I’ve identified one way to do this that would allow me to avoid breaking into those pipes. I could use inflatable test plugs with extension hoses with the whole thing shoved 4ft down through my new drain stub-outs. But the water would be on the “wrong” side of the plug, so I would need to inflate the plugs and then close the hose up inside the pipe with the water and then put a cap on my stub-outs. After the test, I’d have to create a vacuum in the vent pipe with another plug so I don’t have water gushing all over the floor while I remove the caps on the stub-outs to deflate the plugs in the drain lines.

What is the possibility of using a mission coupling say 11/2 or 2″ by 1″ copper or IPS?

When required to put a pneumatic / hydrostatic test (5 PSI or 10 ft head) I also use a balloon type of plug BUT I slip the plug past the pipe opening and use the mission coupling with a nipple and valve.

This way after the test rather then try to vacuum out the remaining water I open the valve slightly using a garden hose adapter and then can dump the water in a place where it wont cause any problems.

Besides a lot of times a decent inspector will ask you to drop the pressure in front of him to make sure you did have the pressure in the system as a lot of *********** cheat with defective gauges or non calibrated ones

[dreamerParticipant]

Sylvan,

Thanks for the reply. Since these are 3″ and 2″ ABS drain pipes, it is just a 10ft head test they will require. So I figured they’d check the vent was full of water since there would be no pressure gauge involved.

I’ve seen the caps with the hose bib on them and they look pretty useful for situations where you have a stub-out at the low point of the run to be tested.

The vacuum I referred to was not to vacuum out the water, it was to hold the water in the pipes while I unplugged the closet flange on the toilet, retrieved the hose for the inflatable plug inside the line and deflated it. Like putting your finger over the end of a straw to hold the liquid in the straw. Just long enough for me to release the plugs downstream and retrieve them, then replace the plugs at the toilet flange and stubouts, release the plug from the vent, and everything would drain away.

My concern with attempting this is not being able to secure the cables on the plugs insode the pipes. If they slip and wash downstream, I’d be in big trouble. How likely is that to happen — considering that they’ll be in the pipes the wrong direction ?

---

Kirk Ellis

[SylvanLMPParticipant]

Hi Kirk, Years ago I used to use plaster of Paris in the main trap to hold back water for testing.

After the test I could eiher chop out the plaster or snake the line with a 2U type of cutter from General spring and wire.

How about a baloon that you can puncture later wih a regular snake.

Isnt plummin fun?

[bungieParticipant]

Why didnt you place test openings where you joined the old lines ??

The old lines are not our problem as they where tested when installed. Just the new lines are your problem.

---

DISCLAIMER

All advice is given with-out seeing the job, and hence all advice MUST be taken as advice with limited knowledge on the exact situation. NO responsibility can or will be taken. And yes, I am a licensed Plumber and Drainer with my own business in Brisbane Australia

[Author]

Posts