Oops, that should be part 21 page 1 fig 1, and drain by lifting the safety valve lever...
c
November 2007
Manually open the safety valve by twisting a quarter of a turn. This will let the pressure off through the vent pipe going through an outside wall. Download the manual from the vokera website. The safety valve is part 20, page 1 figure 1.
c
November 2007
Easiest way is through a drain point on the system.
Mr A
November 2007
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