Worcester Highflow 400 RSF Installation And Servicing Instructions page 17

Mark the wall where the flue will terminate to suit the
installation.
This is the Side Flue Extension centre point position. See Fig. 13.
FLUE OPTION 8. See Fig. 5.
Follow the procedure as described in Flue Option 6 ensure the
flue system remains vertical and horizontal.
Mark the wall where the flue will terminate to suit the
installation.
This is the Rear Flue Upwards Extension centre point
position. See Fig. 13.
FLUE OPTION 9. See Fig. 5.
NOTE: A flue adaptor is required for these flue options.
Refer to Flue Options: 2, 4, 5, 6, 7 and 8.
For installations that require a straight section of flue duct before
the first 90° flue bend, follow the procedure as described in the
appropriate Flue Option. Mark the flue centre point position.
Fig. 13. Marking the flue positions for all flue options.
The position for the hole/holes for the flue should be marked on
the wall/walls.
Drill the flue hole/holes 120 mm (4.5in.) diameter, ensure it is
horizontal,through the wall/walls.
If the internal flue fitting kit is used the hole must be 150 mm
(6 in.) diameter.
Depending on site conditions it may be helpful to pre-plumb the
appliance before moving it into position. Fitting unions or stub
pipes to the appliance pipework should be done at this stage.
Refer to Section 3 and Fig. 3.
Pipework must be arranged to clear the flue system. See Section
5b and Fig. 5.
Before the appliance is fitted to the central heating system,
thoroughly flush the heating system and the mains cold water
supply pipe.
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