Model IGX Make-Up Air
6
®
See charts for duct sizes and straight duct lengths recommended for optimal performance based on AMCA
Publication 201-90. Using duct sizes less than recommended will affect fan performance. Follow good duct
installation practices for the remaining ductwork.
Installation
Duct Sizes
Down Discharge
End Discharge
Housing
Furnace Size
(MBH)
H
W
H
W
12
100
25
23
15
31
150
25
23
21
31
200
25
23
27
31
250
25
23
32
31
22
150
26
25
21
31
200
26
25
27
31
250
26
25
32
31
300
26
25
38
31
350
26
34
39
41.4
400
26
34
39
41.4
500
26
25
32
31
600
26
25
38
31
32
250
26
34
30
41
300
26
34
30
41
350
26
34
39
41
400
26
34
39
41
500
26
34
30
41
600
26
34
30
41
700
26
34
39
41
800
26
34
39
41
1050
26
34
39
41
1200
26
34
39
41