How on earth do I bleed this towel radiator?

[LoveGigi]

We've had a Zehnder Subway towel radiator installed and it's not getting hot except for the bottom 1/3. I need to try to bleed it but I can't work out how this is done. There is no valve that I can see. All there is, is a circular bit at the top on the wall side. See pics. Any help welcome. I have goggled to no avail.

Does that unscrew? It looks threaded try a quarter turn counter clock

Or has the silver bit got a push in cap that pops off

Try twisting the silver thing off. There might be something underneath you can use the radiator key on.
We have a north facing bedroom and the radiator key doesn't fit the radiator. It's freezing in our room

P.S. I'm no Piglet John , Mumsnet's resident expert on all things like this.

You can buy a spanner shaped L like an Allen key bleed key combo.

Thanks for your replies. Holly hope you can sort out your radiator too, it is pretty chilly!

The thing is the silver thing is in a very awkward position. There is about 2cm to the wall and you can't get your hand behind it to manipulate it and the silver thing is also smoothly round so a wrench/spanner wouldn't be able to get a grip of it!

If you zoom in it looks rusty on top of the black powder coated metal making me think it's seepage- a valve.
Rubber bands or nutcracker to grip it?

The bleed is covered by a chrome cap. Just get a small flat screwdriver to flick the cap off.
As your rail is hot at the top and cold at the bottom, I'd say that there is an air blockage that can't be removed by bleeding it.
You might need to empty the rail, reconnect it then fill it back up slowly.
Also, if it is rusting at the top, I'd get it exchanged under the guarantee.

Holly.
If you get an adjustable spanner or a 22mm spanner, you can bleed your radiator by undoing the blank plug.
Just turn it enough for the air to escape then, when water is escaping, close it back off.
Good luck.

Thanks so much for all the help, Testificateman, that silver thing does indeed have a cap which nicely popped off with a small flat screwdriver as you said. I still haven't been able to bleed it as I can't find the chuffing rad key! Will buy another tomorrow, it's also only the bottom that is hot the top is cold so I think it's just in need of bleeding, it also makes a trickling sound suggesting there is space inside the rad for air.

Any time. Pound shops sell them, 2 for £1.