What tool do I need to bleed this radiator?

[YreneTowers]

I'm usually fairly competent. I own several keys for bleeding radiators.

However, it appears that I've never had to bleed the radiator in son no. 1's bedroom, as none of the keys will fit!

Pic attached to show the end of the radiator, where instead of a square shaped hole with a small square bit inside it for the key to fit on and turn, I have a big square bit sticking out. I have no clue what tool I'm supposed to use...

We had a new combi boiler fitted about five weeks ago, and the plumber did a power flush of the system and apparently bled all the radiators, so presumably also bled this one. The radiators all got hot when he tested the system, but when we turned the heating on at the weekend (first time we've needed it) we found that the radiator in this room only got hot at the bottom. The top half of the radiator is cold.

I would use one of these

I'm not an expert but I would say that this end is not the bleeding end.
What does the other end look like?
I'm just wondering if you could change this to a different fitting?

Can't get a pic of the other end as it's behind the bed. That one's just a square hole with no valve, so definitely isn't a bleeding end.

Do you think that maybe some sort of repair was done and the wrong fitting has been put on? Just wondering if you can buy a bleeding fitting instead?

I might just contact the plumber who fitted the boiler and ask him how he managed to bleed the radiator. He did say to contact him if we had any problems...

your boiler installer didn't bleed that radiator.

that's a plug, not a bleeding vent. If you undo it, water will gush out. I can see it is very ols by the rust. It is not the correct part.

there ought to be a vent on the other end.

If there isn't

www.screwfix.com/p/radiator-vent-blanking-plug-chrome-2-pack/40972

the valves at both ends of the rad have to be tightly closed before you attempt to undo the plug. It would be safer to depressurise the system first.

Thanks. The other end of the radiator looks like this (managed to get a pic on my phone). It's almost impossible to see, but there's nothing inside that hole - it's flat and smooth.

The plumber who fitted the boiler told me he had bled all the radiators when he did the power flush, and didn't mention that he was unable to do any of them.

Now I've emailed his boss he may get a rocket up his arse as he also bollocksed up the shower by dropping a washer into the pipe, forgot to put the safety covers on the electrics and didn't put the safety cage on the pipe where it leaves the house (less than 2m from the ground).

the thing at the other end is a "correct" type of iron radiator plug (old style)

newer ones have an external hex and are undone with a spanner (they are also thinner and lighter and are sealed with PTFE tape, not Boss White).

I bet some old plumber broke the real bleed valve years ago, and blocked the leak with an old iron plug from the bottom of his toolbag.

this is the correct wrench for removing the plug with the square hole. With luck you will never need one. They are often rusted in and very difficult to remove

www.screwfix.com/p/radiator-spanner/11467

So if I want to bleed the radiator I basically need a plumber then?

Depressurising the system and replacing the plugs with venting ones doesn't sound like something I want to be trying to do myself. The radiators are decades old and the plugs are painted over and probably rusted in!

Thanks.

yes, a plumber can easily do it. You can order the vents I showed if you want, or get them from a DIY shed at higher price. Get a roll or pack of PTFE tape. The plumber ought to have all these but might charge more for them.

If you have any worn-out vents that do not fit your key well, have those replaced as well.

btw if he had tried to open either of those plugs, they would look scratched and scuffed and the paint would be scraped, even if he was unable to shift them.