Halstead Platinum expansion vessel access

[pauln]

My Halstead Platinum is behaving like the expansion vessel is faulty, the plumber has priced a new one and fitting at about £375, yikes. But he hasn't tested it, and I'm no plumber but have been reading up on this and it obviously needs testing first and the pipe to it may be blocked, so I'm not impressed with him at the moment.

But does anyone know how to access the valve on the expansion vessel - looks like it's probably against the wall at the top and it's all boxed in with the flue at the top, I can't see much in there?! The manual doesn't give any clues either.
Thanks

[wheeto]

You should rely on your expert's erpertise unless you have a reason not to.

If the EV has failed you might find it more cost-effective to have an external unit fitted (if you have the space).

It's not a great idea to be poking around under the cover of a gas boiler without being gas safe, although at least this boiler doesn't operate under positive case pressure.

[pauln]

Thanks, it's ok, I wasn't planning to start dismantling anything myself
Just worrying that the engineer hasn't tested the EV before saying it's broken and it might just need air putting back in it. He said he didn't know how to replace it and was going to find out, but I want him to find out how to test it, so started looking into it myself. There's what looks like a rubber cap on a valve right on top of the boiler, might that be the EV valve?

[wheeto]

There's what looks like a rubber cap on a valve right on top of the boiler, might that be the EV valve?

If it looks like a car / bike tyre valve (ie is a Schrader valve) then you've probably got it. From your description, though, it could also be the cap on an AAV. Any chance of a picture?

[pauln]

Ah yes, that's it, it's more towards the front and a smaller valve.

I'm guessing the EV valve is going to be at the back and the boxing around the flue will need dismantling if there's no other way to access it.