I have the same issue but the screw head had worn out, plumber looked at it before and used a brass key to get around the screwdriver worn head problem...does anyone know where I can find this key ??
Jason G, September 2015
My vaillant Turbomax plus 828e boiler is losing pressure daily - how do i fix this?
Katya, November 2013
Absolutely right, its the 4th from the left. This is not in the manual or anywhere else on the net, thanks.
Basil Vasili, January 2012
cannot find the pressure valve
mo-pink, January 2011
Look underneath your boiler it should have a little key called a filling valve. Get someone to check the pressure gauge as you are filling it up as the pressure should be between 1 and 1.5. If you don't have anyone to check the pressure gauge for you, fill slowly and turn off and check yourself and fill again.
Turn it slowly and fill the unit with water until the required amount has been added, remember to turn it off when you have finished. check the pressure gauge is between 1 and 1.5, Good luck
Claudette, November 2008
look under boiler there are 5 pipes, 4th from left is water inlet, with a flat screwdriver turn valve through 90 degrees and you will hear the water filling the system.
when pressure gauge reaches 1 - 1.5 bar close valve.
you will need cover closed when looking under boiler or you will not see valve