Presure test

I'm testing my water distribution piping at 30 psi air and I have 2 psi per hour drop. What would be a better (than soap solution) way to find the leak? Any Recipe will be greatly appreciated. l

Just dish washing liquid and water. I add some windex to it and it makes large bubbles but it isn't necessary

Why only 30psi? When I tested my system, I intended to go up to 90psi (50% over working maximum). It held fine at 30 psi, but blew out at 45psi after a couple of minutes -- when a CPVC joint I had only primed, but not cemented, let go. Once that was fixed, the system held at 90psi for a couple of weeks. It was interesting to watch the pressure rise during the day and fall at night (the system was overhead in a Florida attic) as the air in the pipes warmed and cooled. I was going to see if the pressure differential actually obeyed the gas laws, but haven't gotten around to that yet .

To answer your question, though, if you're really paranoid about leaks, you can buy or rent very sophisticated "sniffer" leak detectors that depend on a rare gas (usually helium) leaking from the vessel under test. Unfortunately, it doesn't take much of a leak to let helium out -- I don't know if average plumbing, particularly plastic, would contain it or not. I've seen silver-soldered joints in hard copper lines leak helium. Weird stuff. Stick with the Dawn & Windex spritzer test.

leaks

What kind of pipe did you use? If it is copper, do not use a dishwasher soap that has chlorine in it. Use kid's Mr. Bubble or whatever brand your toy store has. As far as the laws governing gas, expansion, and pressure, one factor that would affect it is that plastic can also expand/grow when it gets hot under pressure so the increase in pressure would be less than if it were in a sealed metal pipe.

Leaks

Thanks guys

The piping is copper and I will follow your advices today.

Can you just turn the water on?

hj said:

What kind of pipe did you use? If it is copper, do not use a dishwasher soap that has chlorine in it. Use kid's Mr. Bubble or whatever brand your toy store has. As far as the laws governing gas, expansion, and pressure, one factor that would affect it is that plastic can also expand/grow when it gets hot under pressure so the increase in pressure would be less than if it were in a sealed metal pipe.

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hj, I have never seen dishwashing liquid with chlorine in it but I have seen water with chlorine in it. What does chlorinated water do to copper?

hj said:

What kind of pipe did you use? If it is copper, do not use a dishwasher soap that has chlorine in it. Use kid's Mr. Bubble or whatever brand your toy store has. As far as the laws governing gas, expansion, and pressure, one factor that would affect it is that plastic can also expand/grow when it gets hot under pressure so the increase in pressure would be less than if it were in a sealed metal pipe.

Click to expand...

Why not? Tap water has chlorine!

Jason

Brilliant!

What? Use a kid's bubble-blowing solution to make bubbles? DUH! Why didn't I think of that? Been waaay too long since I was a kid, I guess .