Help Needed Identifying Drain Valve Core

[Terry Fields]

It's getting round to that time where one starts to think of giving the central heating its annual once-over.

The system here is a back-boiler vented type with TRVs on each of the six radiators, and will be 30 years old this year.

There are three 'down' legs from upstairs, there being no horizontal runs between the radiators downstairs.

Each of these - boiler and two rads - have a drain valve. These valves have a core, pictured here:

lower part swivels, and the seal is made by a (now) hard rubber seal with a chamfered seat. As a back-up, and possible candidate for replacement, it might be an idea to have some of these to hand for the maintenance process. There's no maker's name apparent.

Are these still available? And from where? Do they have a name?

TIA

[R]

If you cant get an O ring/Washer to fit why not replace the valve with a more modern equivalent ?

Easier to fix now rather than in the middle of winter when the bugger gives out.

[Heliotrope Smith]

That looks like a knackered flat washer rather than a domed rubber washer.

Over the years they get hard and brittle and start weeping, get tightened down and down and cut into the valve outlet and chop off the outside rim.

Get some drain c*ck washes from plumber's merchants for a few pence each.

This should be done as a matter of course during any drain down. Saves a lot of swearing and cursing when refilling and having to drain down again to replace the washer then start again.

[Terry Fields]

Thanks for the reply.

I'm fairly sure that the seat is also chamfered, it doesn't feel flat when I clean out the valve body.

Gret idea, thanks for the tip.