ROOF INSTALLATION
EXTERIOR-POWER VENTILATOR
DEV900-Exterior Power Ventilator Kit (900CFM
)
(also see instructions supplied with ventilator kit)
1. Locate the blower on the rear slope of the roof. Place it
in a location to minimize duct run. The location should
be free of obstacles (T.V. leads, electrical lines, etc.).
Bear in mind, if the blower top is level with the roof
peak, it will not be seen from the street. Keep this
approximate location in mind as you work from within
the attic.
2. Mark a point halfway between rafters.
3. Drill a guide hole through the roof at this point.
4. From the outside, use the guide hole as a starting
point.
A. Use a T-square to measure 8
1/2
” (21.6 cm) to the
left of the guide hole, then down 10
3/8”
(26.4 cm)
to locate the bottom left corner of the layout.
B. Mark the rectangular cutout and remove only the
shingles in this area.
5. Mark an 11” (27.9 cm) diameter circle centered on the
guide hole and mark the center of the 1
1/4
” (3.2 cm)
diameter electrical wiring hole.
6. Cut out the roof board(s) along the 11” (27.9 cm)
diameter circle and drill a 1
1/4
” hole as marked.
7. For flat roof installations, build a curb that will mount the
blower at a minimum pitch of 2/12. Discharge end of
the blower should be pointed away from prevailing
winds.
8. Remove roofing nails from the upper two-thirds of the
shingles around the cutout area. Carefully lift the
shingles to allow the back flashing sheet on the blower
housing to fit under them.
9. Center the blower ring in the 11” (27.9 cm) diameter
hole, making sure that the 1
1/4
” (3.2 cm) diameter
electrical wiring hold aligns with the hole in the wiring
box.
10. Attach the blower to the roof with the six screws
provided. It is recommended that the screws be
located inside the blower housing. All six holes in the
back panel must be filled, or any moisture that may get
inside the housing could leak into the house.
11. Using a good grade of roofing cement, seal all of the
shingles around the housing and flashing sheet as well
as the mounting screw heads.
12. Bring electrical wiring through the hole in the wiring
box and secure it according to local codes.
13. Make the electrical connections with the proper
connector for the type of wiring being used. Connect
white to white, black to black, and the green or bare
wire to green.
14. Replace wiring box cover and screws. Do not pinch
wiring under the cover.
15. Check for free movement of the damper before
installing housing cover and screws.
16. Turn on power and check operation of the blower.
Guide
Hole
11” (27.9 cm)
dia. hole
71
/
4” (18.4 cm)
11
/
4” (3.2 cm) dia. hole
81
/
2” (21.6 cm)
103
/
8”
(26.4 cm)
201
/
2”
(52.1 cm)
91
/
8”
(23.2 cm)
203
/
4” (52.7 cm)
2”(5.1 cm)
2”(5.1 cm)
7”
(17.8 cm)
29 1/2”
(74.9 cm)
25”
(63.5 cm)
ROOF CUTOUT
REMOVE SHINGLES
Green to
Green
White
to
White
Black
to
Black
120 VAC
Line In
9