On 01/04/2015 15:36, tonkski wrote:
I've noticed a drip coming from a c/h radiator valve connection, and I'm not quite sure exactly what I'm dealing with. Here's a pictu http://tinypic.com/r/fegh85/8

Having Googled around I think there's an adjustable radiator valve tail extension. I'm not sure though, I've never fitted one myself.

The drip appears to be coming from where the adjustable valve tail narrows. The drip seems to be unaffected by the tension of the nut, but does seem to slow if I lift the radiator up.

It's all a bit horrible, with some awkward boxed-in pipework (not me).

Is there a right way to fix this, or a quick way please?

Sounds like the adjustable tail has failed in some way and lifting it
changes the fit of that stem but it could be almost any other part of
the assembly. Adjustable tails normally mean the rad has replaced an
old imperial one, but you can get fixed-length versions ('extending
unions') that should be more robust. You have to get the right length
(smaller is better than longer) but they don't have the slide-y bit that
causes this problem.

It shouldn't take too much to fix:

Cover everything well to contain the inevitable leaks of black gunge.
Close the valves down. Count the number of turns on the lockshield end
(the one in the photo), so you can re-instate it at the end of the job.
Sometimes, a thermostatic valve doesn't close completely (if there's one
on the other end). Taking the head off and putting a spacer under the
control (a penny works well) will close it completely.
Open the bleed valve to let any pressure out, then close it again.
Loosen the union between the valve and the radiator stem (the chewed up
chrome one in the photo) at each end by half a turn or so.
This should let you lift the radiator off its brackets (hopefully there
will be enough play in the pipework) and lay it down without leaking too
much.
Open the unions completely and (with a bit of luck) you can carry the
radiator outside upside down to drain it where you won't make too much
mess.
It would be a good idea to flush the radiator out while it's off or,
depending on its state etc, you may see this as an opportunity to
replace it with a new one.
Put a new tail on, and reassemble.
Open the valves, check for leaks and bleed the radiator to refill it (if
the system is pressurised you'll probably need to add more
water/pressurise the system).