I have had a Worcester Bosch combi boiler for 8months and notice the pressure gauge has dropped to just above zero. The boiler still works OK but when I tried to turn the key underneath the ( Greenstar 2.8i )boiler which is all I was told to do it is so stiff that the key flexes. I am reluctant to apply more pressure. Should I be doing something else and should the boiler be off during this operation ?? Help !!

Taffmo, September 2008

This is information was just what I needed - now we'll be warm! Really helpful - Thanks.

Leigh, January 2010

Thanks guys. Eddie was right. You turn the key to the left, then turn the white (or grey ) knob to the left and water repressurises. When you get to one and a half bars turn knob to right (off) not too tight. Brilliant - problem solved

taffmo, September 2008

You were right not to force it!
I have the greenstar junior 24 -if it is similar the steps are as follows:
Make sure you push the key fully up and turn slightly until you feel that you have engaged correctly - note you can only turn the key a maximum of say a quarter of a turn - (this is probably the position you were at and nothing happened) - what you then need to do is to turn the square white plastic 'thingy' that is next to the key - hey presto - you'll hear water then charging the system!(Unless plumber installed a shut off valve within the supply line outside of boiler).
keep an eye on the level as you fill the system - when upto level turn the square thingy to stop charging the system - turn the key that quarter of a turn and pull out - put things back as they should be and pat yerself on the back for a job well done!
Ed.

Eddie, September 2008

hi turn the boiler off if cold re-pressure to 1 to 1 1/2 bar or if hot 1 1/2 to 2 bar make sure the cold water pipe hasnt got any isolation valves in the pipe work that are turned off other wise u are doing it right probs stiff due to not been used for a while it as a rubber o ring on the key u could take key out and lubricate the o ring with a bit of washing up liquid it may help
regards gary

gary, September 2008