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antipode12
Jul 21, 2009, 10:59 AM
My fiancée smelled a slight gas smell the other day so we called the gas co. Their test found nothing, but I asked to have the line shut down anyway.

Called in a plumber yesterday who pressurized the system and found it dropped from 4 psi to about 3 in 15 minutes.

Went through all of the exposed piping with the soapy mix, and found a few very small leaks in the threading. He removed, resealed, and retightened each one.

Still had a pressure drop.

He had to leave, but we still have 2 joints left to test (they are enclosed in the wall -- I will expose them this afternoon).

Assuming that those two joints do not solve the problem, what should the next step be? How do I find a leak elsewhere? Or could the "repaired" joints still be unrepaired?

Thanks.

speedball1
Jul 21, 2009, 11:56 AM
Here's how you can check it yourself. There's a device you can make yourself. You failed to mention the pipe size so I'm going to assume it's 3/4". You take a 3/4"(or your pipe size) coupling and bush it down to accept a snifter valve. A snifter valve looks like the air valve on your tire except it has threads at the base. Snifter valves can be picked up at some hardware stores and most auto parts stores. Since most air compressures the plug into a cars cigarette lighter have a gauge I would pump up the gas line with that or a bicycle pump with a gage.
OK! Ya got 10 pounds of air in the gas line what now? We check for leaks by taking a mixture of water and dish detergent and painting each joint with it. If you see bubbles then you have a leak. No bubbles and you're home free. Good luck, Tom

KISS
Jul 21, 2009, 01:38 PM
Hey Speedball:

Your new Avatar could use some Crack Spackle. Found some right here:

Long Sleeve Longtail T Crack Spackle - Duluth Trading Company (http://www.duluthtrading.com/search/searchresults/74049.aspx?feature=&kw=crack)

You just jealous because I have a "cute Tush"!!

antipode12
Jul 21, 2009, 08:01 PM
Thanks Speedball, but that's not the problem.

My plumber has the compressor and gauge for the test. (And the bubbles!)

The problem is that have tested 10 joints so far (finding 3 very small leaks) and only have 3 elbow joints left. I am afraid that we will finish and the pressure on the test will still drop.

Is there anywhere else to look for a leak? Do we re-check the joints all over again?

I just want something to suggest when the plumber looks at me and shrugs.

(I'm having a lot of trouble with the techs around here. Seems nobody is thorough or well-equipped. I find myself leading *them* around by the nose.)

KISS
Jul 21, 2009, 08:19 PM
See https://www.askmehelpdesk.com/plumbing/gas-line-test-acceptable-pressure-drop-after-15-min-142944.html

Electronic detection should be better.

Standing pilots on old ranges don't shut off, so there a source of leaks that are not leaks.

speedball1
Jul 22, 2009, 05:33 AM
Antipode, What type of joints are you testing? Copper and compression or black iron and threaded joints. As a rule once the gas line's pressured up the plumber won't leave in the middle of the test without testing all the joints. What makes your job different? Regards, Tom

antipode12
Jul 22, 2009, 02:06 PM
Antipode, What type of joints are you testing? Copper and compression or black iron and threaded joints. As a rule once the gas line's pressured up the plumber won't leave in the middle of the test without testing all the joints. What makes your job different? Regards, Tom

Black pipe and threaded joints.

The plumber got there at 6pm and stayed through 9. His partner took over this morning. I got hosed. Huge.

What happened was he pressurized the line, sprayed the bubbles, and kept finding the most minuscule leaks. Barely noticeable. Like, I couldn't really see them. They seemed like just the natural popping of tiny bubbles. No big leaks, no big bubbles anywhere. (He did not have the same electronic sniffer the gas company had. He pressurized the line to 4 pounds; the meter says maximum of 5.)

So he unthreaded, cleaned, and re-sealed each joint that he saw a leak on -- 4 or so. But his gauge kept dropping pressure to 3 pounds.

This morning, his partner continues with the remaining 4 joints; same story. Finally with one particularly obstructed T-joint left, he decided to try a new gauge, thinking his original one was broken.

Viola! No pressure drop.

So I said "does that mean the other joints were fine?" He says "no" because the soap still showed leaks.

This whole experience has me furious. (Not to mention that the original gas company test did NOT show a leak reading, but because we -- not him -- smelled a slight odor, he locked the gas line until a plumber came out.)

pelle
Jul 22, 2009, 02:38 PM
If the gas meter is on try this.. shut off all appliances at the appliances shut so no pilots are on and nothing con come on. Go to your gas meter there should be a dial called test dial pick the smallest dial i.e.. 1/2, 1 or 2 foot dial. Probably a half on a residential house put a pen mark where the dial is a move away from the gas meter for a while quite a while. The go back and see if there is any movement or rotation. If so go to every joint with soap and water. Also any flex lines like for a range or dryer soap them up with your hand bend them and move them a little bit sometimes they get small cracks if they are old.

massplumber2008
Jul 23, 2009, 03:53 AM
Pelle... thanks, but Antipode is all set here as they have indicated that the gauge was broken and the new gauge showed no leaks... ;)

MARK