Leaking copper joint

[john]

Just completed CH and HW installation in a small flat. Unfortunitly there was one leak on a 22mm tee running on a wall at the back of the kitchen units. This was the one joint where I did not use a heat deflector cloth.. When I opened the joint the solder had not taken at the back.. It is like the heat did not get around the back on the joint. The other thing is the mains stopcock makes a very loud hissing, I wonder how the could be avoided. Does it depend on the size of pipe.

[BigWallop]

If the mains is hissing all the time it is on, then you've got another leak somewhere. If it's only hissing while you're demanding water from taps and things, then this is normal and can't really be avoided unless you find out where the problem part of the system is that is causing the hissing. If you know for sure that the hissing is being caused in mains stopcock you might be able to stop it by using a full bore ball valve with lever arm. But you would have to find out for sure if the valve is actually the culprit.

[mrcheerful]

most likely is lack of cleaning and or lack of flux there. If the rest of the way round is ok then that bit would have been hot enough.

Open the stop valve wide to reduce the hiss.

mrcheerful

[BillV]

I'd aggree with that. The hissing is normally caused by some throttling effect

[john]

" Thanks for the advice :

[john]

"I have opened the valve fully and it solves the problem.

[Broadback]

Don't leave it hard open, back it off just a bit, otherwise it will tend to stick.

[IMM]

Replace it with a full bore valve.