Bosch Greenstar ZWBR 11-25 A31, Installation And Servicing Instructions

A condensate neutralisation kit is available.
The condensate drain pipe and fittings must be made of plastic
(NO OTHER MATERIALS SHALL BE USED) with a minimum
diameter of 22mm.  

The minimum fall for the drain pipe from the open tundish is
2.5° (1 in 20). Where it is not practical to terminate a condensate
drain over a gully then an additional trap should be provided
prior to any connection to a soil and vent pipe (discharge pipe) or
waste pipe (branch discharge pipe).

Any connection to a waste pipe should be downstream of the
appliance trap to prevent any household waste blocking the
condensate drain or causing back flow or back pressure on the
appliance.

Remove the security screw from the right-hand side of the
casing. Refer to Fig.12

Remove the cabinet by pressing both levers backwards to release
and lift off the cabinet. See Fig.12.

Hang the appliance onto the wall. 

Fit the fibre washers to the gas and water connections on the
manifold.

Tighten the service connections.

Flue duct preperation and assembly

Measure the flue length L. Refer to Fig. F5 and F6.

Mark off the lengths shown onto the ducts and cut to length. The
cuts must be square and free from burrs.
Terminal assembly outer (air) duct -  L-750mm

inner (flue) duct -  L-50mm

the measurement is made from the ridge at the terminal
indicating the outer face of the wall. Refer to Fig.F7.
Extension air duct -  L-70mm

flue duct -  L-50mm

The measurement is from the formed end.

Assemble flue system completely. Push the ducts fully together
and clamp in the positions shown in Fig. 2 and 3. The slope of
the terminal outlet must face downwards.
The assembly will be made easier if a solvent free grease is
lightly applied i.e. Vaseline, to the male end of the ducts.

NOTE: An inner wall sealing plate is provided which should
be fitted to ducts before assembly.

Push the assembly through the wall and fix the turret to the
appliance with the clamp. Refer to Fig.F8.

Ensure that the turret is fully entered into the socket on the
boiler. From outside fix the outer wall plate to the terminal and,
after ensuring the duct is properly enclined towards the boiler, fix
the plate to the wall.

If the terminal is within 2m of the ground where there is access
then an approved terminal guard must be fitted. The guard must
give a clearance of at least 50mm around the terminal and be
fixed with corrosion resistant screws.

14

NOTE: THE FLUE MUST BE INCLINED TO THE 

BOILER

L

115

Fig. F5. Flue lenth  rear

NOTE: THE FLUE MUST BE INCLINED TO THE 

BOILER

L

Fig. F6. Flue lenth  side

Fig. F7. Flue terminal position

Outer
Wall
Face

Flue Terminal

Raised Ring
locating the
terminal relative
to the outside
wall face 

Fig. F8. Flue turret

Air and 
Flue Duct 
Entry into
silicone 
rubber seals 

Flue Turret

Clamp

Flue Socket 
on Boiler