"Moz" wrote in message
...

About 40 years ago my Dad pressure tested a DIY plumbing installation
using a car tyre valve (soldered somehow into a 1/2 inch BSP
compression fitting), a foot pump and a car engine compression gauge.
After filling the system with compressed air he left it overnight and
checked for pressure drop.
Does anyone know if this would be an appropriate way to test a plastic
(JG Speedfit) central heating system prior to filling (the gas fitter
is coming to fit the boiler on Tuesday)? I can seal off the open ends.

No. Never test with compressed air. If a fitting fails it can shoot off like
a rocket and seriously hurt.