Help with radiator TRV’s

Albermarle

 I have recently found a number of TRV4s fail, with the chromed "cap" part separating from the rest of the removable head, rendering the head useless.  

With mine the plastic crumbled inside so the whole thing became wobbly ( and stopped working of course) I have had a few do exactly the same.

FreeBear

ThisIsWeird said: When you remove the head, check the pin action, and clean thoroughly around it and its base where it goes down. Then a tiny bit of the sili on your fingertip, and wipe it firmly around the pin's base to leave a complete ring.

Cotton bud or cocktail stick - Saves getting your finger mucky and having little dabs of grease all over the house

Auti

Thank you everyone - you are all amazing

Auti

@ThisIsWeird - followed your instructions and removed head - it looks like this which I find a bit worrying. All that limescale green stuff? This is a radiator that I want replacing (also in room that need decorating). touching the pin it is solid and with the way it looks I am just going to put the trv head back on and look at another radiator!

[Deleted User]

Hi,

you could clean that with old toothbrush and white vinegar or lemon juice, then give pin a 'gentle' tap, or press down with flat blade.

ThisIsWeird

As Frugal says, or you could even tackle that with a wire brush - all the exposed bits are metal.

The green stuff is verdigris - pretty, huh? It does suggest a slightly weep from that valve, but nothing of concern.

If you are going to replace that rad, then best ditto the TRV. But very good chance you could bring it back to life as well, if you wish.

Clean up thoroughly - perhaps wire first, and finish with Frug's idea. Wipe dry. Then the sili grease or PTFE spray (better if you have it - thinner) before gently tapping and pressing the top pin.

You can even slacken that first nut a half-turn to ease the pressure on the pin - that's a 'gland' nut, and squishes a rubber washer with a central hole that the pin comes through. The more the washer is compressed, the smaller the hole become = the tighter against the pin. So a half-turn slacken, followed by lube and gently taps/presses, should get it moving, and once fully free, you then tweak that nut up again to the point no water seeps by, and the pin isn't too sticky.

Auti

Thank you - had visions, if I touched it, that I would cause a flood and not know how to stop it! I have a system boiler (I think it is called) with a water tank in the loft and very little idea how to stop it filling up if I had a boiler system flood (apart from turning off the stop tap under the sink but not even sure if that would do anything quickly). It does look pretty but would prefer it if it was on an ornament outside inside just says leak that could get worse to me!  Cleaning sounds in order …..

FreeBear

Auti said:  - had visions, if I touched it, that I would cause a flood and not know how to stop it! I have a system boiler (I think it is called) with a water tank in the loft and very little idea how to stop it filling up if I had a boiler system flood (apart from turning off the stop tap under the sink but not even sure if that would do anything quickly).

When I had a gravity fed, open vented boiler, there were two gate valve (taps with big read wheels) in the airing cupboard. One shut the water off to the HW cylinder, the other, water to the boiler. But as these never get touched, the one time I needed them they were seized up. Backup solution, tie a bit of string round the ballcocks in the header tank(s) to stop the balls from dropping down.

Auti

@FreeBear - Will remember that and make sure when I put the xmas decs back in the loft I also put a ball of string because s-d’s law will mean I won’t find the string when I need it!