7. ASSESS ROOF THICKNESS
- Measure the roof thickness and
consult the table across to check
if adjustments to the hold down
bolt
and
duct
length
are
required.
Failure to cut the duct
properly can result in
an incorrect seal which
will adversely affect the units
performance
Roof thickness (mm)
Include ‘H’ frame if used
Duct length required
(mm)
Hold down bolt length
required (mm)
125
145 (as supplied)
As supplied
100
120 (cut 25)
As supplied
80
100 (cut 45)
As supplied
60
80 (cut 65)
Cut 50
40
60 (cut 85)
Cut 70
25 (absolute minimum)
40 (cut 100)
Cut 85
8. ASSEMBLE DUCT
- Thread a hold down bar onto
the M8 bolt and push the bolt
almost all the way into the hole
in each corner of the brace
(Fig 9)
- Leave a 10mm gap between the
hold down bar and the recess in
the plastic brace. This will allow
for easier engagement with the
four
corresponding
threaded
holes in the unit.
- Turn the assembly over and add
the extension duct to the top of
the assembly (Fig 11).
- Take care to avoid tearing or
ripping the duct apart.
When
attaching
the
duct to the unit take
care to ensure it forms
a tight, unbroken seal that
doesn’t allow discharge air to
escape.
Fig 9: Insert the four M8 bolts and hold down bars into the corners of the brace
Fig 10: Fit the extension duct onto the brace assembly ensuring a tight, sealed fit
