9
AIR DELIVERY - CFM (Bottom Return With Filter)*
Unit
Operating Mode
CFM Airflow
External Static
External Static Pressure (ESP)
Size Setting
Pressure
Range*
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
040-14
AIRFLOW (CFM)
††
Low Heat
585
†
0-0.60
585
580
585
585
585
580
High Heat
800
0-1.0
800
800
800
800
800
790
780
760
750
735
††
1-1/2-Ton Cooling
525
0-0.50
‡
525
525
505
505
505
††
2-Ton A/C Cooling
700
0-0.90
‡
675
685
695
695
700
700
700
700
700
700
2-1/2-Ton A/C Cooling
875
0-1.0
875
875
875
875
865
855
835
820
795
720
3-Ton A/C Cooling
1050
0-1.0
1050 1050 1050 1050 1045 1020 1010
995
980
965
3-1/2-Ton A/C Cooling
1225
0-1.0
1225 1225 1225 1225 1225 1225 1220 1210 1195 1175
Maximum
1400
0-1.0
1390 1400 1400 1400 1400 1375 1330 1285 1235 1185
060-14
††
Low Heat
500
†
0-0.50
500
495
485
460
430
High Heat
1065
0-1.0
1055 1065 1065 1065 1065 1065 1065 1065 1060 1050
††
1-1/2-Ton A/C Cooling
525
0-0.50
‡
525
525
510
495
465
††
2-Ton A/C Cooling
700
0-0.50
‡
700
700
695
680
680
2-1/2-Ton A/C Cooling
875
0-1.0
‡
850
870
875
875
870
860
845
825
810
805
3-Ton A/C Cooling
1050
0-1.0
1050 1050 1050 1050 1050 1050 1050 1050 1050 1050
3-1/2-Ton A/C Cooling
1225
0-1.0
1210 1220 1225 1225 1225 1225 1225 1225 1215 1195
Maximum
1400
0-1.0
1400 1400 1400 1400 1400 1400 1400 1400 1385 1345
080-14***
††
Low Heat
720
†
0-0.50
720
715
715
720
720
High Heat
1500
0-1.0
1500 1500 1470 1420 1375 1330 1290 1250 1210 1170
††
1-1/2-Ton A/C Cooling
525
0-0.50
‡
525
525
515
505
485
††
2-Ton A/C Cooling
700
0-0.50
‡
700
700
695
695
700
2-1/2-Ton A/C Cooling
875
0-1.0
‡
840
855
875
875
875
875
870
855
850
850
3-Ton A/C Cooling
1050
0-1.0
‡
1050 1050 1050 1050 1050 1050 1045 1045 1040 1030
3-1/2-Ton A/C Cooling
1225
0-1.0
‡
1225 1225 1225 1225 1225 1225 1225 1225 1225 1195
Maximum
1400
0-1.0
‡
1400 1400 1400 1400 1395 1355 1315 1275 1230 1190
080-20***
††
Low Heat
705
†
0-0.50
705
680
680
675
675
High Heat
1500
0-1.0
1500 1500 1500 1500 1500 1500 1500 1495 1485 1480
††
2-Ton A/C Cooling
700
0-0.50
‡
700
670
665
665
655
††
2-1/2-Ton A/C Cooling
875
0-0.50
‡
875
875
875
875
875
3-Ton A/C Cooling
1050
0-1.0
‡
1050 1050 1050 1045 1050 1050 1045 1045 1045 1035
3-1/2-Ton A/C Cooling
1225
0-1.0
‡
1215 1220 1220 1220 1225 1225 1225 1225 1225 1220
4-Ton A/C Cooling
1400
0-1.0
‡
1370 1385 1385 1395 1395 1395 1395 1400 1395 1390
5-Ton A/C Cooling
1750
0-1.0
1750 1750 1750 1750 1750 1750 1745 1740 1735 1725
Maximum
2000
0-1.0
2000 2000 2000 2000 1990 1975 1950 1925 1900 1865
100-20***
Low Heat
920
†
0-1.0
920
915
915
920
920
920
915
900
895
890
High Heat
1525
0-1.0
1525 1525 1525 1525 1520 1515 1515 1515 1515 1515
††
2-Ton A/C Cooling
700
0-0.50
‡
700
700
700
690
685
††
2-1/2-Ton A/C Cooling
875
0-0.50
‡
865
875
870
870
875
3-Ton A/C Cooling
1050
0-1.0
‡
1035 1045 1050 1045 1050 1050 1050 1050 1050 1045
3-1/2-Ton A/C Cooling
1225
0-1.0
‡
1180 1195 1215 1225 1225 1225 1225 1225 1225 1225
4-Ton A/C Cooling
1400
0-1.0
‡
1400 1400 1400 1400 1400 1400 1400 1395 1375 1365
5-Ton A/C Cooling
1750
0-1.0
1740 1745 1750 1750 1750 1750 1750 1750 1750 1740
Maximum
2000
0-1.0
2000 2000 2000 2000 2000 2000 1985 1965 1940 1910
120-20
Low Heat
1180
†
0-1.0
1160 1175 1180 1180 1180 1180 1180 1180 1180 1180
High Heat
1885
0-1.0
1875 1880 1885 1885 1885 1885 1885 1885 1880 1870
††
2-Ton A/C Cooling
700
0-0.50
‡
700
700
700
700
695
††
2-1/2-Ton A/C Cooling
875
0-0.50
‡
875
875
875
870
870
3-Ton A/C Cooling
1050
0-1.0
‡
1035 1040 1050 1050 1050 1050 1050 1025 1005 1000
3-1/2-Ton A/C Cooling
1225
0-1.0
‡
1205 1210 1225 1225 1225 1225 1225 1225 1220 1215
4-Ton A/C Cooling
1400
0-1.0
‡
1390 1400 1400 1400 1400 1400 1395 1385 1370 1360
5-Ton A/C Cooling
1750
0-1.0
‡
1745 1740 1745 1745 1745 1745 1745 1740 1730 1715
6-Ton A/C Cooling
2100
0-1.0
2100 2100 2100 2100 2100 2095 2075 2040 1975 1910
Maximum
2100
0-1.0
2100 2100 2100 2100 2100 2095 2075 2040 1975 1910
* Actual external static pressure (ESP) can be determined by using the fan laws (CFM
2
proportional to ESP); such as,
a system with 1750 CFM at 0.5 ESP would operate at high-heating airflow of 1500 CFM at 0.37 ESP and low-heating airflow
of 705 CFM at 0.08 ESP.
†
Low heat CFM when low-heat rise adjustment switch (SW1-3) and comfort/efficiency adjustment switch (SW1-4) on
control center are OFF.
‡
Ductwork must be sized for high-heating CFM within the operational range of ESP.
** Wattage data provided is for the circulating blower with bottom return and does not include draft inducer, accessories,
or gas controls.
††
Operation within the blank areas of the chart is not recommended because high-heat operation will be above 1.0 ESP.
*** All airflows on 21 in. casing size furnaces are 5 percent less on side return only installations.