Help - leaky valve on microbore rad valve

[goalc]

we have noticed that our rad valve has started leaking, where the inlet pipe (microbore 8mm) goes into the valve. This has obviously started a while ago as the water has been going along the pipe and into the wall, so the plaster is all wet.

We have tightened the nut on the valve as much as we dare (I have heard horror stories about microbore pipes breaking if you put too much pressure on them) but this has not helped.

I guess that I need to take the valve off and either replace the olive, or put something like PTFE (?) tape on it to stop the leak, but to do this I presume I have to drain the system ? The leak is in an upstairs room.

Is there any easier way to do this as opposed to draining the whole system, as I have never done this and understand that with microbore you have to drain all the rads in pairs ? Is there any temporary fix I can apply to stop the leak until we can get it sorted properly ?

Any advice is appreciated.......

 

[ollski]

If you are on an open vented system the best thing is to bung it in the header tank with a bung kit from the plumbing merchants which will hold all the water in the system with a vacuum effect. then undo the rad valve connection to the rad to drain a small pot of water off, tighten that back up undo the leaking joint, apply fernox lsx around the top of the olive (and / or ptfe) reassembe and cross your fingers.

 

[goalc]

thanks for that .......

will I be able to get the bun kit from somewhere like B&Q, as I guess there wont be any plumbers merchants open today ? Also, why do I need to drain a small pot of water out of the rad ?

 

[goalc]

i of course meant bung kit and not bun kit - too busy thinking of hot cross buns !

 

[goalc]

If you are on an open vented system the best thing is to bung it in the header tank with a bung kit from the plumbing merchants which will hold all the water in the system with a vacuum effect. then undo the rad valve connection to the rad to drain a small pot of water off, tighten that back up undo the leaking joint, apply fernox lsx around the top of the olive (and / or ptfe) reassembe and cross your fingers.

sorry - one other question .... when I do this should the rad valve going into the radiator be left open or closed ?

 

[ollski]

I think the kit is called a radiator valve change bung kit, b & q may stock them it's worth a shot and the instructions are in the kit. You need to drain off some of the pressure before the bungs hold, anywhere between an egg cup full to a gallon or so and sometimes they won't hold at all but it makes life easier. You don't need to turn anything off.