How to re-pressurise boiler...Valliant Turbomax Turbomax Plus 824E

[Cowboy10]

Hi,
Recently inherited a boiler in a new place, & noticed over the last few weeks the water pressure
is getting a bit low.. As of today, it's now stooped below 1 bar, so needs topping up fast.
As best as I understand, this model does not needs a filling loop?

The videos I've seen to re-pressurise show two screws to undo, but I only appear to have one??
I undid it a quarter anyway with a flathead, but it didn't do much. (The one in front of the metal plate.)

There is a grey knob on the right, but I'm sure when I twisted it, it kind of hissed & I'm sure the pressure went down further.

I've attached a pic to show the underside of the boiler.

Very different from my last valiant, that was a simple screw to re-pressurise, two minute job. This one has me stumped, however.

Many thanks in advance,
Lee

 

[ianmcd]

Do not touch the grey valve that you talk about that is the pressure releif valve so you have made your low pressure problem worse, towards the back of the boiler behind the plate as you call it just behind the screw that you moved that is the one that you want to open

 

[Phill Peck]

 

[Cowboy10]

Hi Phil & Ian, & thanks for your help.

That is the screw that I opened, except nothing happened...perhaps I didn't open it far enough? Opened it about a quarter, but nothing happened.

Thanks,
Lee

 

[Bunnyman]

Open it half a turn if nothing happens the fill loop or non return are blocked which is common, you will need help with that as they are awkward

 

[Cowboy10]

I've opened the screw half a turn (as far as it will open), but nothing. Looks like I'll need help with the above problem.

Thanks,
Lee