44
A
IRFLOW
1.
CFM in chart is without filter(s). Filters do not ship with this furnace, but must be provided by the installer. If the furnace requires two return filters, this chart
assumes both filters are installed.
2.
All furnaces ship as high speed cooling and medium-speed heating. Installer must adjust blower cooling & heating speed as needed.
3.
For most jobs, about 400 CFM per ton when cooling is desirable.
4.
INSTALLATION IS TO BE ADJUSTED TO OBTAIN TEMPERATURE RISE WITHIN THE RANGE SPECIFIED ON THE RATING PLATE.
5.
The chart is for information only. For satisfactory operation, external static pressure must not exceed value shown on rating plate. The shaded area indicates
ranges in excess of maximum external static pressure allowed when heating. The data for 0.6" w.c. to 0.8" w.c. is shown for air conditioning purposes only.
6.
At higher altitudes, a properly derated unit will have approximately the same temperature rise at a particular CFM, while the ESP at that CFM will be lower.
0.6
0.7
0.8
AC
CFM
RISE
CFM
RISE
CFM
RISE
CFM
RISE
CFM
RISE
CFM
CFM
CFM
HIGH
3.0
1498
N/A
1446
N/A
1368
N/A
1302
N/A
1227
N/A
1145
1059
954
MED
2.5
1223
N/A
1182
N/A
1153
30
1099
31
1051
32
982
901
813
MED-LO
2.0
983
35
971
35
945
36
919
37
878
39
813
746
659
LOW
1.5
816
42
794
43
758
45
734
46
678
50
637
597
523
HIGH
3.0
1494
N/A
1428
36
1362
38
1294
39
1231
42
1162
1076
972
MED
2.5
1203
42
1178
43
1147
45
1101
46
1045
49
986
927
831
MED-LO
2.0
977
52
965
53
939
54
904
57
866
59
801
763
639
LOW
1.5
801
64
786
65
751
N/A
714
N/A
714
N/A
680
635
596
HIGH
3.0
1459
47
1397
49
1339
51
1270
54
1202
57
1107
1049
952
MED
2.5
1191
57
1166
58
1137
60
1086
63
1033
N/A
973
889
797
MED-LO
2.0
985
N/A
967
N/A
932
N/A
900
N/A
859
N/A
805
731
620
LOW
1.5
808
N/A
785
N/A
758
N/A
726
N/A
679
N/A
629
590
513
HIGH
5.0
2115
N/A
2050
N/A
1973
35
1915
36
1810
38
1695
1587
1467
MED
4.0
1802
38
1739
39
1725
40
1665
41
1612
42
1532
1443
1320
MED-LO
3.5
1517
45
1509
45
1496
46
1475
46
1441
47
1388
1304
1205
LOW
3.0
1213
56
1225
56
1216
56
1194
57
1179
58
1135
1084
1005
HIGH
5.0
2284
30
2231
31
2170
31
2103
32
2037
33
1945
1836
1750
MED
4.0
1865
37
1869
36
1775
38
1732
39
1684
40
1619
1548
1480
MED-LO
3.5
1594
43
1571
43
1530
45
1492
46
1454
47
1414
1355
1293
LOW
3.0
1411
48
1366
50
1325
51
1296
53
1251
54
1200
1147
1096
HIGH
5.0
2082
41
1997
43
1943
44
1847
46
1749
49
1669
1560
1443
MED
4.0
1823
47
1782
48
1711
50
1659
51
1574
54
1513
1402
1305
MED-LO
3.5
1565
54
1545
55
1529
56
1487
57
1441
59
1365
1287
1196
LOW
3.0
1261
N/A
1237
N/A
1242
N/A
1216
N/A
1179
N/A
1145
1098
1034
HIGH
5.0
2137
40
2073
41
2031
42
1949
44
1879
45
1811
1734
1625
MED
4.0
1793
48
1754
49
1704
50
1648
52
1590
54
1534
1451
1371
MED-LO
3.5
1558
55
1518
56
1477
58
1425
60
1376
62
1316
1242
1170
LOW
3.0
1370
62
1325
64
1288
N/A
1237
N/A
1191
N/A
1134
1086
1024
HIGH
5.0
2256
45
2192
47
2133
48
2054
50
1986
51
1907
1834
1718
MED
4.0
1805
57
1762
58
1722
59
1677
61
1618
63
1563
1507
1441
MED-LO
3.5
1565
65
1513
N/A
1480
N/A
1415
N/A
1392
N/A
1346
1269
1198
LOW
3.0
1368
N/A
1326
N/A
1278
N/A
1238
N/A
1208
N/A
1165
1093
1052
HIGH
3.0
1400
N/A
1331
N/A
1263
N/A
1189
N/A
1106
31
1020
941
843
MED
2.5
1204
N/A
1176
N/A
1121
30
1072
32
1002
34
927
853
740
MED-LO
2.0
1020
33
998
34
968
35
923
37
880
39
820
739
652
LOW
1.5
841
41
827
41
797
43
766
44
727
47
680
634
556
HIGH
3.0
1668
31
1335
38
1288
40
1207
42
1133
45
1061
955
845
MED
2.5
1224
42
1182
43
1139
45
1088
47
1015
50
948
859
759
MED-LO
2.0
1030
50
1005
51
988
52
942
54
893
57
830
751
666
LOW
1.5
859
60
830
62
815
63
789
65
751
N/A
693
629
556
HIGH
4.0
1770
39
1645
41
1610
42
1528
45
1437
47
1340
1251
1141
MED
3.5
1690
40
1615
42
1531
45
1470
46
1393
49
1308
1196
1099
MED-LO
3.0
1612
42
1540
44
1472
46
1398
49
1306
52
1223
1132
1010
LOW
2.5
1396
49
1339
51
1304
52
1250
55
1170
58
1092
1010
906
HIGH
4.0
1793
48
1699
50
1610
53
1533
56
1461
58
1363
1247
1146
MED
3.5
1693
50
1622
53
1552
55
1467
58
1390
61
1320
1205
1083
MED-LO
3.0
1632
52
1546
55
1493
57
1415
60
1332
64
1257
1148
1054
LOW
2.5
1429
60
1380
62
1334
64
1258
N/A
1199
N/A
1136
1041
942
0.1
0.2
0.3
0.4
0.5
*MSS920402BN
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