On Oct 2, 9:37 pm, wrote:
Have a plumbing problem. Made some modifications to hot water copper pipes
in basement, then refilled with water, well found a couple of leaks...so had
to drain whole system again and made repairs..before I refilled with water I
filled with air at 30lb pressure..seemed to be ok so let air out and
refilled again and still have one very small leak...this is on a 1" T
fitting that I had very hard time getting to because of location...the T
fitting seems to be just a shade bigger than the 1" copper pipe I am
soldering into it...one side that I have not touched does not leak..whoever
soldered that side seems like they kind of soldered in a way to build up
solder along edge of joint..and so no leak there...anyway I have just
repaired again and have pressurized with air at 30lbs pressure and once
again can not find any leak...but I am afraid I will refill with water and
get pressure up and find same leak again.

couple of questions....

1. is there some liquid I can place over repair that would help to detect
pinhole leak?

2. if there is still leak how can I solder so as to build up solder on edge
and make better connection?

When soldering pipes, you must allow for the expansion of air inside
the pipe as the pipe heats up or it will blow through the joint.
The solution is to leave the pipework open at all radiators and boiler
to allow the pressure to disburse.
When finished fill with water, pressurize, and see if it leaks.
If it does leak, you must remove all water inside the pipe for some
distance either side of the joint, otherwise the water will boil and
add itself to the air expansion and blow through the joint, even if
you leave the ends of the pipes open, there is always the chance of a
water blockage inside the pipes leading to internal pressure.
Perry