Author Topic: Pressure Testing Shut Off Valves  (Read 2871 times)

Offline Admin

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Pressure Testing Shut Off Valves
« on: December 09, 2015, 10:38:02 AM »
I had a TSSA inspector point out something I did not know.  I attached a picture of a 1/2" shut off valve which happens to be stamped 1/2PSI.  He says you are not allowed to subject these shut off valves to a 15PSI pressure test, unless they are left open and capped.

I was at the Lennox wholesaler today and noticed their 1/2" yellow shut off is rated 123PSI.

It would be much easier to pressure test using the 123PSI shut off as it can be left closed.

Quote
Clause 6.18.1 - A manual shut-off valve shall be of the plug, ball, or eccentric type, and it shall not be subjected to either a temperature or a pressure greater than its certified rating.

Offline bster352

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Re: Pressure Testing Shut Off Valves
« Reply #1 on: December 10, 2015, 07:59:37 AM »
At Noble we sell the Fairview valve. It is stamped 1/2 psig but it is rated up to 5PSIG. Check the specs online or ask your wholesaler for a spec sheet that you can carry around in your vehicle if challenged. I know it is not rated for 15 psig but just pointing out the inspectors don't know everything.

Offline bster352

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Re: Pressure Testing Shut Off Valves
« Reply #2 on: December 10, 2015, 08:55:28 AM »
We also carry the BMI and it is rated to 125psig.

Offline Admin

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Re: Pressure Testing Shut Off Valves
« Reply #3 on: December 10, 2015, 10:48:01 AM »
That's great thank you sir!

Offline Porcupinepuffer

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Re: Pressure Testing Shut Off Valves
« Reply #4 on: December 10, 2015, 03:00:02 PM »
Funny how I've always noticed the 1/2 psig stamped on these for years, but somehow never linked it over to the 15 psig pressure test as a possible issue.

I wonder why if even with the valve open it would still be allowed to be subjected to over 1/2 psig. if it states 1/2 psig, wouldn't that mean in all forms of pressure relating to the valve, be it open or closed cannot exceed that rating?  Is the 1/2" psig really specific to only one side of the valve in the off position?
Maybe TSSA still allows it that way since most of the valves out there would need to be completely removed from a system to do a completely legal pressure test?

Offline Admin

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Re: Pressure Testing Shut Off Valves
« Reply #5 on: December 10, 2015, 03:14:07 PM »
I thought the same thing, but the TSSA inspector did say the valve could be left open and capped.  But you're right I believe it's the seam in the body that would be compromised, and not the internal valve that opens and closes.  Either way I will make sure to purchase the 123 or 125PSI shut off valves to avoid any issues.

He also mentioned that the seam, on the shut off valve, should always be installed towards the appliance.  I know I've cracked one open in the past by being careless with the wrenches.

Ultimately the Code says the shut off valve should be removed,

Quote
6.22.2  Before appliances are connected to a new piping and tubing system containing fittings or joints, a   pressure test shall be applied using either air or an inert gas (e.g. nitrogen) in the following manner:  (a)  Appliance shut-off valves, meters, regulators and any component not rated for the test pressure being applied shall not be connected to the piping or tubing system under test.