look under the bottom of the boiler for 2 white taps these taps are connected via a silver braided pipe (filler loop) proving the loop pipe is there you open the tap on the right 90 degree turn followed by the left tap the same you then watch the gauge rise to just under 1.5 bars as it gets close to this get ready to turn off both of the taps now bleed the lowest rad free of air, put more water back in the system move to the next rad and repeat (air out water in) till all rads have been done.
you can down load a manual from Vaillant web site along with the room stat setting up/ pairing info.
wirecutterman, October 2010
