Rheem 27 Owner's Manual And Installation Instructions page 70

FLUEING
6. Horizontal flue runs between bends must have a
minimum upward gradient towards the flue terminal of
20 mm per metre.
Note: Ensure that the seam of the inner flue in horizontal
runs is towards the top of the installation.
Secure each flue component using the sheet metal
7.
screws provided.
Fix a Wall Bracket after each transition to a vertical run.
8.
This is to prevent vertical loading on the bends and
offsets.
9. Support vertical sections of flue at a distance no greater
than 2 m using a Wall Bracket (PN 295128).
Note: The Wall Bracket can be used to support vertical
sections of flue from a ceiling by rotating the legs through
90°.
10. Install an Adjustable Straight Length (PN 295127) if a
special length is required between offsets or changes in
direction of the flue.
The Adjustable Straight Length can be adjusted
from 560 mm to 890 mm by pulling on its end to
increase its length or pushing on its end to decrease
its length.
Firmly tighten the compression band on the
Adjustable Straight Length to prevent the pipe from
extending or compressing its length over time.
Fit a Trim Ring over the last section of flue prior to
11.
penetrating the ceiling, if one is to be fitted.
Once all of the flue components, excluding the Vertical
12.
Terminal, have been installed and all supports are
securely fastened, the roof flashing must be installed and
adequately sealed to prevent rain entry.
Cut the flashing to a diameter that allows a snug fit
over the flue.
Install the roof flashing over the flue and using
suitable fasteners, fix to the roof material.
The flue must extend a minimum of 150mm through
the roof flashing.
13. Connect the Vertical Terminal (PN 295117) to the flue
exiting the roof.
Secure the joint with sheet metal screws provided.
The top of the Vertical Terminal should not be less than
450mm above the flashing below.
Observe flue terminal clearances in accordance with
AS5601. Refer also to
on page 59.
Note: The flue should not extend more than 1.5 m from
the roof unless guy wires or other additional support is
provided.
"Vertical Flue Terminal Location"
70