System boiler hot water tank - bleeding

[Nedman87]

Hello all, good day!

I had to drain down our system boiler the other day to cut/modify some pipework for a bathroom radiator to towel rail change out. Bathroom is on 1st floor so I closed all other lockshields and tvr's upstairs. Drain point was above ground floor pipework.

It looks like I forgot about the hot water tank! I'm unsure if much water would have come out of the coil but I definitely heard what sound like trickling water/bubbling at the tank when the hot water was turned on from the boiler.

There are these fittings on the feed and return to the tank which I'm assuming are bleed points? They appear very tight and I'm reluctant to try and force them open. Any advice would be appreciate to how I can bleed or check the system for air?

Thanks

(Excuse the socks between feed and return, without them the pipes can make a loud resonance noise. I have some lagging to fit to insulate/cushion.)

 

[Exedon]

Yes that's the air release valve (Yorkshire rv35)
Has a screwdriver slot but regularly need grips instead.
That's a Dowty washer in it they sometimes leak for fun.

 

[Nedman87]

Yes that's the air release valve (Yorkshire rv35)
Has a screwdriver slot but regularly need grips instead.
That's a Dowty washer in it they sometimes leak for fun.

So should I just try and get it to open or a chance il shear it off?

Or are these supposed to auto vent air?

I can't see how they manage that if so

 

[denso13]

Not auto, loosen it to bleed, as above, then retighten.

 

[Nedman87]

Thanks all, will give that a go later today