30
*SK - DOWNFLOW GAS FURNACES - 80% AFUE
Model
Number
Heating
Input
(Btuh)
Motor
Speed
External Static Pressure (Inches Water Column)
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
CFM
Rise
CFM
Rise
CFM
Rise
CFM
Rise
CFM
Rise
CFM
Rise
CFM
Rise
CFM
Rise
SK054(†)-23A
54,000
High*
1,375
29
1,340
30
1,300
31
1,270
31
1,225
33
1,175
34
1,115
36
1,035
39
Med-High
1,155
35
1,130
35
1,110
36
1,085
37
1,055
38
1,015
39
975
41
910
44
Med-Low**
790
51
775
52
765
52
750
53
730
55
700
57
665
60
610
66
Low
650
62
640
63
630
63
610
66
590
68
565
71
530
75
480
83
SK072(†)-24B
72,000
High*
1,610
33
1,590
34
1,575
34
1,560
34
1,540
35
1,495
36
1,460
37
1,415
38
Med-High
1,295
41
1,275
42
1,260
42
1,250
43
1,220
44
1,195
45
1,170
46
1,120
48
Med-Low**
1,155
46
1,135
47
1,115
48
1,095
49
1,065
50
1,040
51
1,015
53
980
54
Low
910
59
885
60
860
62
835
64
810
66
785
68
765
70
735
73
SK090(†)-24B
90,000
High*
1,675
40
1,655
40
1,640
41
1,620
41
1,590
42
1,560
43
1,520
44
1,475
45
Med-High
1,330
50
1,315
51
1,300
51
1,280
52
1,255
53
1,230
54
1,200
56
1,150
58
Med-Low**
1,180
56
1,165
57
1,150
58
1,135
59
1,115
60
1,090
61
1,060
63
1,010
66
Low
940
71
925
72
900
74
880
76
850
78
825
81
795
84
760
88
SK108(†)-35C
108,000
High*
2,395
33
2,335
34
2,285
35
2,230
36
2,200
36
2,140
37
2,080
38
2,000
40
Med-High
2,190
37
2,135
37
2,115
38
2,080
38
2,030
39
1,975
41
1,915
42
1,810
44
Med-Low**
1,785
45
1,770
45
1,740
46
1,725
46
1,685
47
1,645
49
1,615
50
1,565
51
Low
1,145
70
1,110
72
1,070
75
1,035
77
1,000
80
950
84
905
88
835
96
SK126(†)-45D
126,000
High*
2,445
38
2,395
39
2,385
39
2,330
40
2,275
41
2,225
42
2,130
44
2,015
46
Med-High
2,195
43
2,170
43
2,140
44
2,120
44
2,090
45
2,030
46
1,975
47
1,855
50
Med-Low**
1,795
52
1,780
52
1,770
53
1,760
53
1,725
54
1,690
55
1,655
56
1,610
58
Low
1,480
63
1,475
63
1,450
64
1,440
65
1,440
65
1,415
66
1,405
66
1,375
68
Notes
(†) “C” = Standard Models
“N” = 80% Low NOx
1. Temperature rises in the table are approximate. Actual temperature rises may vary.
* Factory Set Cooling Speed
2. Temperature rises shaded gray are for reference only. These conditions are not recommended.
** Factory Set Heating Speed
Table 5. Maximum Airfl ow and Temperature Rises (°F) - Downfl ow Gas Furnaces
