Baxi Solo 2 60 RS Installation And Servicing Instructions page 17

Installation - Page 17
Fitting the Wall Mounting Plate
Secure plate to wall using 63mm (2½ in) screws.
From outside building, pass air duct through wall opening. The
two tabs should be positioned at the bottom.
Slide air duct over inner duct until tabs contact wall surface.
Ensure air duct is horizontal and square to wall face. Using
sealing tape supplied make good the joint on inside of the two
ducts.
Make good with cement mortar between the outside wall and
duct.
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