Installation with fan package extension, Step 1 roof opening, Step 2 install roof curb – Greenheck KSF (457646) User Manual
Page 4: Step 3 install curb extension, Step 4 install ductwork
4
Supply
Ductwork
by Others
Exhaust
Ductwork
by Others
B
C
D
A
E
D
A/2
Curb
Footprint
Roof
Opening
C
L
C
L
C
L
Exhaust
Duct
Supply
Duct
Support Legs with
Extended Weatherhood
Exhaust
Supply
1 in. Inside
Flange
installation with Fan package extension:
step 1 roof Opening
Determine the center of the exhaust and supply duct
roof openings. The chart below shows the maximum
recommended roof opening dimensions. These
sizes can be smaller based on codes and ductwork
sizes.
step 2 install roof Curb
Center curb over roof openings and place on the
roof. Level the curb and shim if necessary. Attach
curb to roof and flash in place.
step 3 install Curb extension
Install curb extension over curb, use wood screws
to lag in place. Prepunched holes are provided.
Locate extension so the tall, louvered side is over
the exhaust opening, as shown in illustration.
step 4 install Ductwork
exhaust:
Exhaust ductwork must be built in
accordance with NFPA 96 and any local
codes. Ductwork terminating at the fan
should be square in shape or of smooth
transition so as not to to affect the fans
performance.
supply:
The chart at left shows the duct sizes
and straight lengths recommended for
optimal performance (AMCA Publication
201-90). Using duct sizes less than
the recommended lengths will affect
fan performance. Good duct practices
should be followed for the remaining
ductwork.
Before beginning this installation.
When locating this unit, make sure that there is room to
access the unit from all sides. The inlet must be located
at least 10 feet away from any exhaust vents.
Housing Size
#1
#2
#3
A - Max. Roof Opening
25
35
47
B - Max. Roof Opening
61
83
105
C - CL
to CL
of ducts
36
48
58
D - Duct CL
to Edge of Opening
12
1
⁄
2
17
1
⁄
2
23
1
⁄
2
E - Supply Duct CL
to Support Legs CL
96
89
1
⁄
2
80
1
⁄
2
All dimensions in inches.
Recommended Supply
Ductwork Sizes
Blower
Size
Duct
Size
Straight
Duct
Length
108
13 x 13
37 in.
109
13 x 13
37 in.
110
14 x 14
47 in.
112
16 x 16
54 in.
115
20 x 20
68 in.
118
24 x 24
81 in.
120
26 x 26
96 in.