internal leak sealer

[aaoplumb]

hello.

i have a small leak in a pretty inaccessible place (would need to knock through a stud partition wall to get to it) in the return pipe from the hot water cylinder. it's located at the site of an isolation valve. i've tried fiddling with the valve but it still leaks. are the internal leak sealers like fernox super concentrate any good or advisable to use? i really don't fancy re-doing the wall!

many thanks in advance for any advice.

 

[corgiman]

worth a try, but if its more than a weep chances are it will do anything

good luck though

 

[aaoplumb]

thanks for the rapid response! it's really pretty slow, perhaps one drop a minute when the hot water's on. can't do any harm to try it - can it? that's my main concern, it buggering things up.

 

[aaoplumb]

that should be b*gg*ring, not b*****r!

 

[chrishutt]

can't do any harm to try it - can it?

Leak sealer (LS1) might possibly block TRVs and other elements (especially on modern boilers) which have narrow waterways. Best to avoid it except as a last resort.

 

[aaoplumb]

hmm, that sounds a bit worrying. i can just about get to the leaking part at arm's length. is an external sealer of any use?

 

[chrishutt]

Can you post a picture of the leaking valve? Or describe it in more detail?

 

[aaoplumb]

afraid i don't have my camera at present (lent to my sister for her hols!).

i'm not sure i'm necessarily using the correct terms (i.e. "valve" vs. "stopcock"). however, the leaking part is basically a red circular metal tap. it's attached to the pipe by a nut on either side. if you screw it fully in, no water gets beyond it, if you open it up the water flows freely beyond it. it looks a lot like this:

http://www.inspiredheating.co.uk/acatalog/midbras-fire-valve.jpg

but the tap at the top is red.

 

[aaoplumb]

aha! better picture:

http://www.wessingtoncryogenics.co.uk/Needle Valve.jpg

is almost exactly what it looks like.

 

[chrishutt]

A gate valve. All you have to do is tighten (clockwise) the gland nut (on the spindle).

 

[aaoplumb]

many thanks indeed!