UKC

I've got a leak from the bathroom towel rail radiator. Rather than having a normal TRV it's got a shiny looking tap. This tap is now leaking. How do I fix it?

Here's a photo:

http://tinypic.com/r/25kklxz/9

It's leaking where the tap 'spindle' goes through the nut that my finger is resting on, just in front of my fingernail. I've tried nipping up the nut but it was already snug and didn't make a difference. The top of the tap says 'Heritage Bathrooms 1924' if that makes a difference.

I would like to avoid draining the central heating system if at all possible! It dribbles slowly when the heating is on. I think it's drawing air in when the heating cools down again, as I occasionally get a rumble/kettling noise from the boiler which goes when I bleed the air out of the heat exchanger.

Thanks.

In reply to NottsRich:

Carefully slacken off just the nut you have finger on, so you can wrap several turns ptfe tape around spindle and tighten up nut again to pack down tape??

In reply to NottsRich:

It's the stem seal on the valve. Either strip down and replace the o ring, or replace the valve. Either way, drain down to below the level of the valve. Sorry.

In reply to paul_in_cumbria:

I thought that might be the case... Thanks for confirming. I had considered taking the stem out and quickly shoving a bung in the hole, with a few towels on standby. Replace the seal on the stem and then put it back in. Granted I won't have access to the sealing surface to give it a clean. Is that a stupid idea not worth considering further, or worth a shot?

Speaking of seals, are they standard sizes or will I have to get an assortment and try them all? Any way of predicting what size/type it will be?

Jim, thanks for the idea. Not too sure on the construction inside the valve, but I don't t think that would work. Happy to be corrected!

Thanks UKC.

In reply to Jim Hamilton:

I recently did a stoptap using this method very successfully. Note that you need to roll the PTFE tape up into a "string" rather than leave it flat and push it down into the body of the valve.
This video shows what you need to do except you won't have to remove the tap head because you can get at the offending item without removing anything.
youtube.com/watch?v=udlENiipBCU&
You shouldn't need to drain the radiator to do this although it might be wise to close the valve first!

In reply to Jim Hamilton:

Yeah; looks like it needs repacking. Undo the nut, and re-pack with wool daubed in Vaseline...

In reply to NottsRich:

A long shot but have you tried fully opening the tap?
Our stop tap leaks but if you fully open it then it stops.

In reply to NottsRich:


It'll spray mucky water *everywhere* no matter how fast you are. Drain it.


Strip it while the plumber's merchants are open and have a back-up plan (blanking caps!) if you can't get the parts you want that day because you'll likely lose hot water while your central heating is drained and in bits while the shops are closed and that makes you unpopular at home as I've learned over the years. New valves won't be expensive but putting it all back together leak free is in my experience an annoying iterative process involving several sessions of draining, filling, bleeding, testing, swearing....!
jk

In reply to MeMeMe:
Or at some other position is worth trying - my main stop tap only leaks when fully open. Any other position is fine!

In reply to jkarran:



This is the best advice. Do the job when the plumber's merchant is open and likely to stay open. Don't use a cheapo Chinese valve as they don't shut properly.

In reply to NottsRich:

Try repacking first but if you decide to replace the valve, cheap enough, if you have a valve the other side of the rad, close that, release the pressure and freeze the pipe you're working on. Then you can catch the drain off from the radiator, won't be more than 2-3 litres. Saves draining the system.

If you can't isolate it can you freeze both ends?

Even if you drain the entire system you don't need to drain the boiler, as you should be able to isolate that at the boiler.

In reply to NottsRich:

We had a couple of iffy radiator taps - they would leak if fully open, but not if tightened just a bit. We live in a hard water are and so a weeny drip soon clogs if left to its own devices. if it's a proper leak, then drain and replace.

Thanks all, some useful comments in there. I think I'll try the re-packing method first (thanks pec, I'll give it a go but not sure if it will 'fix' the right bit of the valve) and if that fails get someone in to fix it. There's another faulty TRV (stuck open) and I have no idea what condition the water is in. I'll drain a bit and have a look at it, and if it's grim I'll get someone in to drain/flush/replace and do the valves at the same time. If it looks clean I'll go DIY and try not to make a mess of it!

I tried as pec and others suggested. Success! Glad I had my hand over the tap handle though, because when I undid the gland nut it tried to fly out of the valve body. It ended up needing two pairs of hands to do it, but overall a success - thanks ukc!