Adding new gas line & pressure test causes leaks?

[Nolan Kienitz]

Interesting situation I'm experiencing:

Plumber adding gas line for a cooktop being changed from electric to NG.

Single-story house built in 1982.

Black iron gas distribution. Meter in alley, gas entrance to house about 40-feet run underground. Underground feeder may be poly with iron risers ... will learn for sure today.

Extension to cooktop is also black iron.

Local AHJ requires a higher pressure test with system changes ... not a bad thing.

Pressure test not holding and plumber is finding that some of the old/original connections seeping. Has been segmented (so far) with leaks at underground feeder at in-house distribution.

Higher PSI possibly blowing past some old connections. (supposedly)

Will be learning more as more testing begins anew today.

Any wise thoughts from the massive experience here at TIJ?

BTW - Yes, this is my home.

.

[Nolan Kienitz]

UPDATE: Gas line repairs at my house

Poly connection to bottom of riser (at house) is/was leaking. Typical riser with black tape wrap on riser, over coupling and poly. Leak right at poly and coupling.

Riser also had small diameter pipe as support from original construction that was a water conduit along and to bottom of black iron riser wrapped in tape that also has rusted. Support pipe was just under roof eave where runoff would almost hit it directly. (Think about it ... how many times do we see that?)

New 'weather-sealed' riser with longer horizontal stem is being installed to replace defective. Here's hoping the other end at the meter is still OK. At least it is not under the eave of the roof, but still has the hollow pipe for support of the original riser.

One great learning experience, but my checkbook is likely going to hurt when it is all over.

Gas leak is at poly to coupling:

Click to Enlarge

60.89 KB

New riser being installed:

Click to Enlarge

66.04 KB

Hollow pipe along riser at meter:

Click to Enlarge

84.16 KB

.

[inspector57]

Nolan, is there any relationship with the leaking part and the ones causing all the explosions on homes in the area? I think all of these were supposed to be part of the gas companies pipes at the meter risers but just thinking out loud.

[Nolan Kienitz]

I wish the leak was on the utilities' side of the meter. Unfortunately it was not.

Dunno if this leak would be part of such concerns or not.

.

[Brandon Whitmore]

What is the required test pressure?

Usually, the required standard pressure ("w.c.) test pressure is only 10#'s for 15 min, but most guys around here pump up to 25'ish pounds, and I rarely see a leak.

I witness and sign off on the gas line pressure tests at times, but don't have any experience with re- pressure testing older lines. There's no requirement to re- test them around here.

[Nolan Kienitz]

What is the required test pressure?

Usually, the required standard pressure ("w.c.) test pressure is only 10#'s for 15 min, but most guys around here pump up to 25'ish pounds, and I rarely see a leak.

I witness and sign off on the gas line pressure tests at times, but don't have any experience with re- pressure testing older lines. There's no requirement to re- test them around here.

BW -

Turns out they use same values here.

Plumber did run pressure up to 25+ when he happened across some seepage in a legacy connection from when the house was built in 1982. He started to get a tad worried as he has seen some situations over the years where there had been a mess of leaks in some legacy properties.

He segmented the system and then also found the underground failure at the riser/poly connection where it comes up to enter the home (as noted ... our meter is in the alley about 40' distant).

City of Plano (AHJ) requires pressure test on situations such as our case where a new line was being installed for an appliance (in our case a cook-top).

Actually with any appliance change (water heater, furnace) and adding a line for an appliance the AHJ would have also required the plumber to install sediment traps at the W/H and furnace if they were not present. They also check the appliances for adequate combustion air and proper venting ... if not present you get 'red-tagged' until updated.

This is interesting to see and hear about as a few years ago the City of Plano AHJ could have cared less about 'sediment traps'. Interesting how the pendulum swings.

.

[Brandon Whitmore]

I wish there was a requirement to re- pressure test older lines when new work was done-- a bunch of leaks would be tracked down & fixed if they did so.

At my day job, we don't check for sediment traps on gas lines during inspections, but I do when performing home inspections.