I am installing a new gas line (Black iron) for propane boiler and I would like to pressure test. What's the best way to do this... what psi and for how long?

In the area I live, the city requires a 24 hr test at 50psi. This may vary in your location so call your building code dept. If you are rural and don't have one, then call a plumber. They should have the answer.

Tony sounds about right about the test. We test our threaded joints by putting the line under pressure and painting the joints with liquid detergent and check for bubbles. We also install a drip loop next to the meter and slope out pipe back towards the meter to trap any moisture before it can snuff out the pilot light. Good luck, Tom

Boy... I'll tell you... Tony said it... CALL YOUR LOCAL PLUMBING INSPECTOR and ask him what pressure gas pipes are tested at in your area.

In my area... we test residential pipes at 3 PSI for 15 minutes or so BUT we use a special gas pressure gauge that reads in 1/10th pound incremements.

So... call local inspector and see what they require for gas test...just tell him different plumbers told you different things when they dropped by to look at future work.

Then here, we drip leg each appliance (this is a tee fitting with a 3.5" nipple and cap in bottom of tee to collect condensate. A drip leg is really just the last elbow going into the propane boiler but with a drip leg). The gas pipes all pitch toward a drip leg (toward the appliance).

So as you can see... done different, but done very similar in many areas.

I think in your case, I would test at 25 PSI for 24 hours because you probably won't have the special gauge I talked about.

Be sure not to let this excess pressure get anywhere near the gas meter or any of the other appliance or boiler GAS VALVES!!! The inside of these meters and valves are simply not designed for this pressure and will break if subjected to excess pressure.

And that is really only reason I popped in... to warn you not to let excessive pressure get to any other appliances or the meter like I mentioned! If testing entire system... disconnect from meter and disconnect from the appliances at the union fittings and then cap these for the test.

After successful test, reattach all and should be all set!!

Good luck with it all... MARK

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