PEX A Pressure Test

[Jonathon Zetterholm]

What should be hooked up when I pressure test the system? Right now I have shower valves, ice maker hookup, and laundry hookup connected. It holds air pressure (80+ psi) for several hours, but drops to below 20 psi after 24 hrs. I'm assuming I want it to hold better than that. Should I cap off the lines before all those valves and test again? Or do I just need to spray everything down with soapy water? Any suggestions? There are no audible leaks anywhere.

 

[Terry]

It holds 80 for several hours? I would try it with water then.

 

[Sponsor]

 

[Jonathon Zetterholm]

It holds 80 for several hours? I would try it with water then.

It is new construction, no heat, no insulation yet. I am in the Midwest with sub-freezing temps every night. Testing with water makes me a little nervous. Is PEX a that resilient?

 

[hj]

The tubing is, the fittings are not.

 

[Jonathon Zetterholm]

So, I have tested a couple times now up to 100 psi. It drops slowly (over several hours) to around 60-80 psi. Some of that is due to pex expansion, I know. But then after letting it sit overnight it drops to 15 psi and stays there. Shower, laundry, and ice maker valves are installed. Are these the problem or do I most likely have a leak at one of my connections? Seems like they are pretty hard to mess up.

 

[Kreemoweet]

Air compressors put out HOT air. When that air cools down, pressures in a closed system will drop dramatically. Air testing is
the pits. It's dangerous, and many places is not acceptable to pass inspection. Test with water, and then blow the pipes
clear with air if you're worried about freezing.