[?] Worcester-Bosch Greenstar boiler - pressure adjustment.

[David Chapman]

We recently had a new Worcester-Bosch Greenstar boiler installed and when it was commissioned the CH system was pressure-flushed and checked OK. I was told by the installer that the system normally runs at 1Bar pressure and was shown the white tap and square-headed screw underneath the boiler which are used to readjust the pressure if it drops. Unfortunately I didn't pay enough attention to this at the time and now I cannot remember the correct way to top-up the pressure.

I found that there was some air in one of the radiators a few days ago and when I 'bled' it out I noticed that the boiler pressure reading has dropped slightly so I would now like to correct things.

I'd be most grateful if one of this NG's experts could tell me the correct way to use the white tap and square-headed screw to re-pressurise the system. I'd also appreciate knowing how much the indicated pressure readings should vary between the boiler being idle and when it is supplying hot water drawing a bath,

Many TIA - Dave

[stuart noble]

I posted this a while back. It refers to a 24i junior but maybe yours is the same

"Just for the archives, the built in filling loop for this boiler operates as follows: Shove the plastic key up into the hole to the right of the white plastic nut, turn clockwise (it locks at about half a turn). Then turn the white plastic nut anti clockwise to fill the boiler"

IIRC it needs a bit of force to get the key all the way into the hole

[geoff]

On my 28iJunior, I didn't like the position of the filling loop, so I left it on and kept my old filling loop arrangement