More Tube view (mytube.com?)
part of the testing of the tubes after you lay them out is to pressurize them with air. The company we got our stuff from sent nice testers for this process, so we've been going through them, and I was told you could re-use the brass couplings between the PEX and the copper... well, that doesn't seem to be as accurate as I'd like.
We pumped up one run three different times, each time losing more than 10lbs overnight. (from 50) After worrying that we'd have to search for a pinhole leak, I finally switched up the pressure tester and it worked fine. In other words, it was most probably the joint at the PEX. and yes, I made sure to have good, clean tubes with no burrs and good, straight joints with well tightened nuts. Now I'm going to have to call the company and ask for new couplings.
Above you can see the 'tube test' area, which will eventually have the pumps and valves and the water supply. Note the bicycle pump on the left. We don't have a power air compressor, so we were doing it the old fashioned way, by hand.
In the meantime, work on the kitchen floor continues.