Minor radiator leak

MaxP779 · 13 Aug 2013 at 19:52

http://i.imgur.com/Eqzs4uH.jpg

Its just a slow drip but it started out of nowhere, heating hasent been on since May. Likely just needs tightened more right? Why did this happen?

Ive been toying with the idea of replacing all my TRV's with drayton TRV4's but it'll have to wait until the system is drained when the new boiler is being put in.

Attu90 · 13 Aug 2013 at 20:03

Tightening that part wont solve the leak as its just the top part of the valve, you should be able to unscrew the TRV without any water coming out but it looks as though the valve has failed.

Id just replace it, it may stop leaking when you turn start using the heating again and the valve is back in use but it may just get worse.

Nightglow · 13 Aug 2013 at 20:06

TRV4's best trv's available, got a box of 10 of them, off Freecycle last month.

Back to your leak, a strange place for it, if you remove the head, is the black piece in the valve body, screwed fully in, seen them come loose.

Sometimes the O ring on the base of the plunger fails, & lets water pass, & it comes out where you mention.

MaxP779 · 13 Aug 2013 at 20:14

Ive looked more, turning it on causes it to leak much faster and i was wrong about where it was leaking :eek:

Ive updated the picture to show where its coming from, yeah its not that metal thing after all.

Dont know how to take the head off, any tips?

MaxP779 · 13 Aug 2013 at 20:23

Okay ive taken it off, this is what im looking at:

http://i.imgur.com/vmFTiea.jpg

Water seems to be coming from that thing right in the middle, which bit needs tightened here or is it humped?

Jokester · 13 Aug 2013 at 20:26

If it's coming out round the plunger in the middle it's goosed.

Edit: Might be worth seeing if you can push it down and see if it reseals correctly, but if that doesn't help you'll need to replace it I suspect.

MaxP779 · 13 Aug 2013 at 20:33

Jokester said:
If it's coming out round the plunger in the middle it's goosed.

Edit: Might be worth seeing if you can push it down and see if it reseals correctly, but if that doesn't help you'll need to replace it I suspect.

Aye TRV4 replacement it is then. Ill just try and seal it for now.

Yeah ive noticed i can push it down, is it supposed to stay down or???

Light taps with a wrench makes a small amount of black stuff come out.

RJC · 13 Aug 2013 at 20:36

Looks like the shaft seal has gone, they should bounce back up once pushed down.

Nightglow · 13 Aug 2013 at 20:37

Yes, it's meant to go up & down, then when you have trv head on, your opening & closing the valve.

MaxP779 · 13 Aug 2013 at 21:08

Would it be fine if I super glued the leak shut for now?

Nightglow · 13 Aug 2013 at 21:42

Use a 1/2" brass blank cap in place of the trv head, will need a few wraps of ptfe tape on the valve body thread to give a water tight seal.

And don't over tighten it.

http://www.toolstation.com/shop/Plumbing/Compression/Brass+Cap+12/d20/sd2697/p39682

EDIT: Some of the older trv's were larger & required a 3/4" blanking cap.

MaxP779 · 13 Aug 2013 at 22:25

Cool thanks, ill get both types and see what fits.

Renton · 13 Aug 2013 at 23:25

I agree with the others the seal to the valve stem has failed, replace it now, you dont need your heating system atm so get it done, other wise you will forget about it until winter when you actually need it and a potential draining of the system is a much bigger deal

summer is the time for heating maintenance