Hello All

I had got a permit to extend my existing gas line to my kitchen so that I can change my stove from electric to gas. I got the plumber to get the new line to the kitchen. Once the new line was completed, I shutdown the values of the gas to other appliances in the house.

I got a new gas gauge to check if the gas line holds to 10PSI as per the code. When I plugged in the gauge to the new gas line and opened the main gas value, I checked with my plumber to see if there are any gas leaks using soap+water and there was no leaks on the new pipes.

But when I checked the gas gauge, it remained at 0 PSI. I pressed on the knob on the side of the gas gauge and I could smell the gas flowing into the gauge.

Can someone please tell me how to go about the gas pressure testing procedure that needs to be done for inspection?

I checked couple of discussions and I would like to confirm if my understanding is right.

1. Pump up the gauge to 10 PSI by injecting air via the small knob with the help of the hand pump (which we use for pumping air into the tires of the car or any other vehicle).
2. Once the pressure reaches 10PSI. close the knob and connect the gas gauge to the gas line (after shutting down the gas value)
3. Once the gauge is connected, open the gas value and check if the gauge holds steady at 10PSI for the next 10-15mins with the inspector onsite.
4. Check for leaks on the existing gas pipe for any leakages.

If these steps are right, how does the gauge remain at 10PSI, after I pumped air in it? I mean how do we know that the gas flow is keeping the 10 PSI and not the air I had previously pumped in via the air hand pump to keep it at 10PSI in the first place?

Please let me know your comments and thoughts and let me know your suggesstions.

Thanks

You turn off the gas valve, either at the meter or where it comes into the house. Also turn off the valves at any other gas appliances you have. Install the gauge onto the line. Pump up the pressure on the line to the required pressure. Wait for the inspector. You don't open the gas valve. The gas line has only about 2 or 3 lbs of pressure on it. If you open the valve at the meter, the air you put in your piping will simply go up the gas line and the pressure will return to the 2 or 3 lbs. of the system. I don't know what kind of gauge set up you purchased but it sounds like you have a gauge, a valve for pressurizing, and a shut off valve. Install the gauge on the system, open the shut off valve and then pressurize the entire system.

Hi all:

When testing gas at 10 PSI you need to DISCONNECT the gas meter and spin it so the meter bar outlet can be capped/plugged. If you don't do this, most likely, the diaphragm at the meter will burst due to the excessive pressure introduced... remember, these meters are only meant to carry 1/2 PSI... ;)

Then you are supposed to disconnect all the other appliances at the union fittings and cap off each line. Why? The same reason as above... at 10 PSI if a shutoff fails it could blow the diaphragm of the gas valve at the appliance... an expensive mistake to fix if it occurs!

Then you would install a shutoff and then the test appuratus at the appliance/piping to be tested.

With the shutoff open, pump the pressure to 10 PSI and then shut the shutoff off. Wait 10 minutes and open the shutoff... any change in the reading on the gauge? If so, a leak is present and will need to be found by pumping the pressure to say 25 PSI and then soaping all up to find it.

Be careful NOT to pump the pressure up with the shutoff closed as that will simply blow the gauge... always check to be sure the shutoff is open.

Anyway, that's how we test here in Boston where we are all licensed plumbers and licensed gas fitters.

Let us know if you have questions...

MARK

Mark

Since he is really only testing the additional piping, can he just turn off the valve where the line comes into the house?
I guess a better question would be, shouldn't the plumber doing the work have set this up?

Hi Harold

The main gas shutoff is installed on the inlet piping to the gas meter. In this case, if he only shuts the inlet shutoff he would be testing right through the gas meter (via the outlet piping) and at 10 PSI could burst the diaphragm as mentioned. There is almost never a shutoff on the outlet side of the meter. If there was an outlet shutoff then shutting this would work fine... as long as the shutoff gets completely closed off and even that is a bit of a guess with older shutoffs so we are taught to ALWAYS disconnect the meter. Fact is that if a gas company determines that a diaphragm got burst due to excessive pressure then the homeowner or plumber pays for it.

I know this all sounds like overkill, but it is how to test a gas system at any pressure without blowing the diaphrams to any gas meters or gas valves... ;)

For example, if he determined a leak is present using this method of testing, then he could simply pump pressure up to 25 or even 50 or more PSI with no concern for hurting any appliances.

I really only wanted to present a correct testing method for future readers... :)

I would also agree that the plumber should have performed this test!

Have a great day! Off and running here...

MARK

Hi All

Just want to recap what I had seen in this discussion. Many thanks to Mark, Harold for valuable inputs.

1. Shutdown the values to all the appliances in the house including the new gas line to kitchen.
2. Shutdown the main gas value.
3. Connect the gas pressure gauge to the gas line.
4. Pump in up to 10PSI on the gauge from the knob provided on the gauge.
5. Verify if the gauge is holding good at 10PSI.
6. Open the main gas valve to the house.
7. Open the gas valve of the kitchen and check if the pressure is holding good at 10PSI for 10-15 minutes
8. Check for leaks on the line.
9. Open the gas valves to other appliances to see if the gas pipe is not leaking else where.
10. Once the gas pipes are checked and verified for no leaks, then shutdown the gas valve on the kitchen and remove the gas pressure gauge and connect the new cooking appliance to the gas pipe.

NO,NO,NO.

Do not open valve to meter with 10 lbs of pressure on piping.
Mark has just explained that that much pressure will damage meter.

You can only do this if you have a shut off valve between you and the meter. In other words only if you have valve to turn off gas inside the house. And only if you have valves at each appliance to turn off gas to that appliance.

You are pressurizing the piping, the piping only, to see if you have a leak.

Are you doing this for an inspection or for your own satisfaction?

Hello Harold

I am doing this for getting the inspection ready scheduled this week.

I have a shut-off valve on the new gas line along with individual valves to the other appliances (water heater/central air).

Sorry for being such a novice in this, but can you please tell me step by step instructions that I need to follow for getting ready for inspection.

Thanks

No Problem...

Most important here is to stop mixing the gas and air... not necessary and will damage something costly if you keep doing it!

Follow this list and you should be all set:

1) Disconnect the meter from the meter bar and cap the outlet as directed at post #3... see image again. This is critical to success.

2) Disconnect all union fittings to each gas appliance and cap these (remove the 1/2 union fitting and cap line). You could also shut off the shutoffs, but as stated earlier, if you have a leak past a shutoff it could damage a gas valve or even damage the appliance.

3) Install test apparatus with shutoff and gauge at new piping to appliance.

4) Pump the system up to 10 PSI and hold for 20 minutes. Once confirmed all is OK you will need to schedule for inspection.

5) Pump system back uyp and stand for inspection... pass inspection... ;)

6) After the inspector signs off on the test you can depressurize the system by opening the shutoff at the appliance and removing the test apparatus (do this slowly).

7) Reconnect the gas meter and all the appliances (or turn on shutoffs you shut off).

8) Double check all connections that you disturbed to be sure ALL unions/fittings have been re-tightened.

9) Turn on gas at gas meter now.

10) Bleed gas off at the farthest appliance by loosening the union fitting until you smell gas (shouldn't take too long). Re-tighten union. This expidites lighting the pilots.

11) Bleed off gas in same manner as above at any appliance you disconnected. Be sure to let gas dissipate before lighting the pilot(s) in next step!

12) Light pilots or test that stoves ignite at each burner, etc.

13) Sit back and have a beer... :) Job well done!


Good luck!

MARK

Show us a picture of you meter. Do you know what union fittings are? Look to see if you have a shut off valve inside the house.

Mark, don't mean to muddy waters but I think he is gong to have trouble capping line at meter. How about detail instructions.

I agree Harold... :)

Here is more detailed instructions on capping/plugging meter... see image. Most important with all this is for Bahomeowner to use two wrenches on everything he touches and to also to know if this is over his head... ;)

Thanks...


MARK

Yes, Maybe he will show us a pic. I just check my meter and I have a union just before it goes through the wall. In my case I would get another union with a nipple and cap. Loosen at the union, swing meter away and plug with spare union , nipple and cap.

Maybe he will have a valve inside and can just turn that off, and disconnect at the meter yoke. I don't have a valve inside but one of my rental properties does. That's why I keep asking "Do you have a shut off valve inside?" A little concerned that the more he un-pipes the more trouble he will have getting everything sealed back up.

Yeah... all good points!

As usual, a bit more to it then it appears! I would really prefer to see his plumber do all this!

Thanks Harold...

Yes, a lot more than it appears. I'm very cautious about gas, don't want to wake up one morning 10,000 feet in the air.

Mark,

You stated every thing very well, But one thing that I will ask,after Bleed off gas at every appliance and connected don't you think that a soap+water test be needed it is just a question, Thanks.

John


Mark,

I have seen the leak checks to be done like the picture bellow, what do you think of this, you need to cap all the appliance shut off valves, thanks.

John

Hi John:

Bahomeowner can install the test apparatus at the meter or the appliance... both work equally well... ;)

In terms of soap testing after bleeding... can't hurt for sure! Most important will be for bahomeowner to use two wrenches at every union and he should be OK!

Thanks...

MARK

Hi All

Sorry for the late reply. I was busy with some stuff around here. So basically I did the following as per your recommendations.

1. shutdown the main gas valve. (Did not remove the flange as I thought I will do a quick test)
2. removed the gas line from the water heater and central air.
3. inserted the pressure gauge to the new gas line.
4. Now I tried to pump the air from the right side as per the above pic.
5. The air pressure did not go up at all.
6. I tried this for the close to 30mins.
7. I could not check for any leaks but I will do it again.
8. I am attaching the picture of our gas meter.

Please let me know what I am doing wrong.

Thanks

TanveerC:\Documents and Settings\traza\Desktop\Picture 022.jpg

Cannot see your picture. It looks like that pic is on your computer and your computer is not available to me.

Post a reply, at least two characters,
Click on the Go Advanced button.
Scroll down to management attachment,
Click on Manage Attachments button,
Click on Browse. Find pic on your desk top.
Click on open.
Click on upload.
Click on Submit Answer

Attached are the pictures. Can you please take a look at it and let me know your comments...

I think it would be best if you called your plumber back and had him set up the test and call for the inspection. There is just too much un-piping at the meter for you to do. Even if you successfully disconnected the piping form the meter and capped the line you would have to reconnect every thing and there are to many places to have a leak. It will cost you for this of courses but there is just too much risk. By the time you purchase the tools and material to seal off the piping you will have spent 50% of what the plumber will charge you.

Yep, its time to get the plumber back in to do a proper test. Gas really isn't something to be taking chances with. I would suggest having them do a complete system pressure check, not just the new gas line. Once they are there, you might as well have them pressure it all up and find and fix any leaks they find. Mark is dead on for testing system. We unhook from meter, then put on a fitting that has a gauge with scrader vavle (actuall gas testing gauge) then disconnect all appliences at unions and cap. We actaully test at 20 pounds for 15 minutes(I know, overkill but overkill is better than kill). Then once test holds and is approved, reconnect meter and appliences, then soap all joints that did not under go pressure test(unions that were capped, meter spuds, gas valves, pilots tubes etc,) just to make double sure. Also a good idea to spray complete shutoff valves at each applience, as they do have a tendency to leak at stem.

Long story short,, bahomeowner, get a pro into take care of this for you. I don't mean to be a drama queen, but it could be a matter of life and death.

Hi Harold

Even the last test I did was with my licensed plumber and I am going to do that this weekend.

I just want to make sure that the test I did today and posted in this discussion thread is correct and would like to know everyone's comments and suggestions.

Thanks

I hope you don't mind if I jump in with my 2 cents... You already got excellent responses above...

1. It is much more difficult to test entire gas system, meaning old and new piping. Some Inspectors will allow you to test only the new part but I understand that may not be the option in your situation. To test only new pipe, you would start with Gas Rated Ball valve at the point of connection with old system and continue to the new location. Then, you can just shut off the ball valve, put gauge on the other side of the new pipe and pressure it. ( Btw: This ball valve has to be accessible and if inside the wall, access door must be installed ) But I understand some Inspectors will ask you to test entire gas system prior signing off final inspection.

2. It is difficult to test entire system the way you are attempting to test it. As other Experts already mentioned above, do not test the gas meter.

3. You have to remove all gas valves and install rigid pipe caps on each of its location. Gas valves used to connect appliance with gas flex may not hold 10 psi. Most of them are rated for less. The valves we are using are rated for 3 psi. Therefore, if you leave them on the pipe they will slowly release pressure giving you the reading you are getting.

4. Also, since you are testing entire house system, you could have a small leak anyplace in the system. This leak may not leak under regular pressure on house side ( 0.3 psi in my area), but will leak when pressurized to 10 psi.

5.It is difficult to trace old leaks since you may have leaking joint somewhere inside the wall, in crawls space hidden behind a joist, or in the attic covered with insutalion. That's why we always try to test only the new work.

It is certainly a job for professional plumber, not for a HomeOwner.

Let us know how you did... Interested to know how you solved this problem... Good Luck... Milo

Hi All

I really appreciate all your experts response to my question.

I had done all the above test with a professional licensed plumber. We had modified the gas line to add an extension for the cooking range. Once we verified the leaks, we wanted to pressure test the line. We inserted gas gauge on the end where it was going to be connected to the gas range, and pumped in air from end after shutting down the main valve. We had removed the gas lines to appliances (water heater and central air to avoid any issues as per the experts advice in this forum). We did not remove the gas line near the main gas valve as we did not want to break it or damage it right now. After the preparations were done, we started to inject air from the other end of the gauge and still the reading was at 0. We changed a different gauge and still the same problem.

Any suggestions please...

Thanks

Did you disconnect gas meter and plugged the pipe before it goes into your house ?

Did you use compressor to pump up the system ? Or hand pump ?

Hi Milo

No that's the only thing I did not do as the licensed contractor thought the pipes being old might cause some other issues and decided to do it later.

We used compressor to pump the air into the line.

Thanks

You are doing this with the assistance of a licensed plumber?

Yes - All my tests were done and reported in this thread was with a licensed contractor.

But is he a plumber?

He is a general contractor.

You really need a licensed plumber on this one. If you didn't disconnect meter you most likely have already damaged meter. Its this simple,, if gauge doesn't go up at all, there is a serious leak somewhere. I wish you the best of luck, not much more we can do for you from here. Take care. Lee.

Gas meters in my area have pressure regulator installed on left side of the meter. The regulator reduces incoming gas pressure to 0.3 psi. If you happen to have such a pressure regulator on your gas meter than all pressure you are trying to put in is most likely escaping through the regulator.

I agree with MGD77: call licensed plumber, journeyman. He'll know how to deal with it. It is gas you are dealing with so you want to be 100% sure all is tested properly.

Hi All

Sorry for not updating you the status. I finally got the contractor to plug the lines that are connected to my appliances. I also removed the main connection near the meter reading and plugged it as well. I installed 2 guages one near the main line and the other near the other end of the new gas line in the kitchen and pumped in 10PSI air into the line.
I waited for 15mins and I noticed small drop in air pressure maybe it went around 9.8 or 9.9PSI. Is that acceptable as per the standard testing.

Thanks

Bahomeowner

Such a small drop in pressure is acceptable. It may be caused by pressure equalizing across the system and / or by differences in temperature as the pipes run throughout your house. But you are definitely on the right tract.

However, if it continues steady decline, you should investigate. Leave it pumped up for 30 minutes and see how low it will drop.

I personally find any drop whatsoever in fifteen minutes unacceptable. I would do as Milo says and retest for thirty minutes. If pressure keeps dropping, pump system up to 50 pounds or so and soap all accessible joints.

Hi All

I tested multiple times and I noticed that the pressure is held at 10PSI for 15-30 minutes but it drops down over a period. I mean if I look at 1hr it will be at 9.8PSI and so on.

Does it mean the pipes are leaking?

Thanks

Tanveer

Hi All

I would really like to thank you all the experts for their valuable guidance and patience in answering my questions. I finally got the gas pressure test passed. The inspector finally approved the pressure test. I followed the instructions as provided by the experts in this forum and it really worked.
I have one last question to ask - I need to get the mechnical final inspection where I have been told to get the appliance in place and call for inspection.

Can you please let me know what needs to be done...

Thanks

BaHomeOwner

Well, I wouldn't think so. What are they going to inspect, it's a stove not a furnace. Call the local building office, but I would think the gas inspection should be all that is needed.

They do it when they are slow. Inspector wants to see a gas shut off valve installed on each appliance and also wants to see the type of gas flex you used. That's all. This inspection will be only a formality. Inspector should be in 'n' out in 2 minutes.

I had the gas range right in place - I told the inspector I can hook it up and keep it ready. He just took only 5mins for the gas pressure test. He told me call for another inspection and that is costing me 100dollars.

Thanks

Bahomeowner

Are you sure you have to pay for it ? It should be covered by the cost of the permit. Maybe you should call Building Dept. and ask...

Hi all:

If it hasn't already been mentioned, don't forget to install the ANTI-TIP DEVICE. This anti-tip device as well as the shutoff and the correct flexi. Connector are what the inspector looks for... ;)

Glad you're all set!

MARK

Hi All

I finally got the mechanical inspection done and approved and I am all set. I would like to take this oppurtunity to thank all the experts and their invaluable guidance to helping me pull through and getting the final approval with this permit.

Thanks a lot and your help...

Bahomeowner.

Glad to hear things worked out.

Thanks for the info.

Hello all. I'm in a simlar situation as bahomeowner. I'm finishing my basement and I've installed a gas fireplace. Luckily there is a gas fireplace above it on the main floor and when it was installed the builder left one side of a tee valve capped off for a basement fireplace if desired. I've installed the fireplace with no issues and ready for the air pressure test.

Like an idiot, I tried to pressurize my gas pipes (from the new fireplace location) without first plugging the gas line at the meter (I simply turned off the intake valve). I sat there forever wondering why no air pressure reading would register on the air gauge, while I'm sure air was simply spewing out of the regulator outside.

I have a pretty standard gas meter (no meter bar across the top). I plan to disconnect the outlet union, plug it, then conduct my test.

My questions:
Mark mentions using TWO wrenches when disconnecting the union fittings at the meter... why?
I assume the union fittings are compression? And they don't require pipe dope when reattaching?

The meter appears to still be working OK after blowing tons of air the opposite direction through it... I'll keep my fingers crossed!

Thanks!
DJ

..

Some very valuable information here.

I just had a gas line installed (professionally) and have a few questions.

BTW - It has already passed inspection.

How long does it need to hold the 10lbs of pressure. Is it acceptable to have 10lbs of pressure and over 3 days have it drop to 5lbs? This is what mine has done. The weather here in Colorado does fluctuate quite a bite if that matters. Has been quite cold at night and warms during the day. I am hesitant to install the gas stove and potentially have a leak...

Thanks in advance for your help.

Allen

OK guys stop here, Allen has also figured out not to piggyback on a 4 page post of someone else. He has asked this question in a new post

But I love piggyback rides.

I am also in the process of performing a pressure test for inspection. I have "Two outlets"
Can some one please highlight the steps? It was never listed.

(Also some extra questions just incase)

1)Do I pressure test from the meter-- The Pipe connected to the outlet pipe (Do I have to remove the union on the meter outlet)

2)Do I have to perform the test from the end of the lines before the appliance but after the shut off before I connect the appliance.

3)Can I pressure test from one of the ends of the new lines and have an appliace connected to the other new line outlet with its valve shut off.

I sincerely appreciate a response.

Milo - very old thread here, not sure f you are still around, but when you said:
"Gas meters in my area have pressure regulator installed on left side of the meter. The regulator reduces incoming gas pressure to 0.3 psi. If you happen to have such a pressure regulator on your gas meter than all pressure you are trying to put in is most likely escaping through the regulator. "

Does that regulator work both ways, in other words if the pressure test was started at the end of the new run, pushing air back up to the meter, will this regulator do the same thing, and expel the excess? I have read others say that you can blow the diaphragm on the meter, but are they talking about the ones without this regulator?

Amopower, welcome back. Yes, I am still here...

Gas meter, and everything on the LEFT side of the meter belongs to the Gas Company. You don't submit gas meter and / or plumbing LEFT of the gas meter to pressure test. You do test gas pipes on the right side of the gas meter.

If this is remodel, and gas meter is installed, you just unscrew right union connecting gas meter and house plumbing, and either cap off the house end or put pressure gauge on it and pressurize the house side. You DO NOT put gas meter under pressure.

I cannot really talk about whether pressure regulator will hold or expel pressure when pressurized backwards as I have never done it nor was I ever required to do such test. In fact, I am not even allowed to do such test on City's equipment. Same applies to the gas meter.

Hope that explains

Milo

Yes, thanks a lot for replying. Luckily for me, when I tried to pressurize without disconnecting the meter, I could not get any pressure to register at all on the gauge, it was like the line was entirely open. (read 0psi while trying to pressurize slowly). I am confident nothing was ruptured, it never had a chance to. I suspect this is the same situation as the guy in post 4, the air would just escape through the regulator. I will go out and get a union, nipple and cap for the right side of the meter and do it the right way. Hopefully there's nothing special about the existing union to the meter where I would be unable to get a matching one.

Yes, thanks a lot for replying. Luckily for me, when I tried to pressurize without disconnecting the meter, I could not get any pressure to register at all on the gauge, it was like the line was entirely open. (read 0psi while trying to pressurize slowly). I am confident nothing was ruptured, it never had a chance to. I suspect this is the same situation as the guy in post 4, the air would just escape through the regulator. I will go out and get a union, nipple and cap for the right side of the meter and do it the right way. Hopefully there's nothing special about the existing union to the meter where I would be unable to get a matching one.

One more detail: If you have already installed gas valves ( gas cocks ) at each appliance - remove them and cap off the end of the pipe with a pipe cap. Most of the gas valves will not hold pressure - especially the aluminum ones - as they are designed to hold only about 3 PSI of pressure.

Good luck with your test !

Milo

Thanks, yes I had read that above as well. I find it a bit ironic though that in order to pressure test the new run, you have to disconnect several older runs, possibly introducing NEW leaks you never had before. (but yes I understand very well why it is mentioned, if the valves are possible leak points themselves, then you cannot really test with confidence). It's too bad the fuel gas code does not mandate valves with stronger pressure capabilities, so that opening up lines can be avoided. Seems odd to me too that you have water valves that can withhold up to 180psi, yet the gas valves are so much lower.

For years, we use ball valves rated for Natural Gas at each appliance. That way we can install all appliances before inspection is done, close valves, and run the test. After the job is inspected, we just open ball valves. No tools needed

These ball valves are rated for high pressure.

Also, when connecting new gas line to existing gas line, we always install ball valve at the point of connection. That way, we don't have to mess with disconnecting and reconnecting gas pipes. Again, we close ball valves isolating new and old and open them after inspection. Note: every valve has to be accessible. So if it is buried inside wall, you will need to install service door. But it is OK in places like under the house where such is easily accessible

Hope that helps

Milo

Thanks Milo. I didn't realize the ball valves were not what you were referring to when you mentioned gas valves (gas cocks)... Both the appliances here have what appear to be ball valves leading to them (they only turn 90 degrees).
I couldn't put a valve right at the new line beginning, as the new beginning is in a crawl space and I understand valves need to be accessible. (although I would still have one at the other end - the appliance end - but reading the code I think they mean ALL valves need to be accessible, even the unnecessary ones.)


I am on hold with the pressure test for now. I got the meter couplings undone, but when I tried to remove the nipple/couple on the outlet side to insert a capped nipple in its place, I was worried about the force I was applying to the coupling nipple and it was still not moving. (perhaps it has been there since the house was made in 1968). Last thing I want is for something to crack, but I have no idea what is "normal" in terms of how much force you need to apply, so I am waiting for another more experienced guy to come over tomorrow. It's galvanized and doesn't look corroded, but who knows what the insides are like.
(AC-250 meter)

Well I got the test done, found two leaks in the process (dropped 2psi in 15 min), tightened the fittings further, and I am now maintaining 15psi for 15 minutes and counting, so I think this was a success! Very glad I did this the right way, with the pressure test, and then upped the pressure to 25 psi and used soap to narrow down the two leaks, because one of them was in the crawl space. Thanks Milo for the invaluable help!