10
AIR DELIVERY -- CFM (BOTTOM RETURN WITH FILTER)*
Unit Size
Operating Mode
CFM Airflow
Setting
External Static
Pressure Range*
External Static Pressure (ESP) In. W.C.
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
060---14
††
Low Heat
635†
0---0.50
635
635
625
615
615
High Heat
1070†
0---1.0
1070 1070 1070 1070 1070 1070 1070 1070 1065 1045
††
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 1045
3---1/2---Ton A/C Cooling
1225
0---1.0
1225 1225 1225 1225 1225 1225 1225 1225 1225 1205
Maximum
1400
0---1.0
1400 1400 1400 1400 1400 1400 1400 1400 1380 1325
080---14***
††
Low Heat
900†
0---0.50
860
870
880
885
885
880
870
855
850
845
High Heat
1245†
0---1.0
1245 1245 1245 1245 1245 1245 1245 1235 1190 1145
††
1---1/2---Ton A/C Cooling
525
0---0.50‡
515
495
490
475
465
††
2---Ton A/C Cooling
700
0---0.50‡
685
680
670
665
665
2---1/2---Ton A/C Cooling
875
0---1.0‡
830
840
850
860
860
855
840
830
825
820
3---Ton A/C Cooling
1050
0---1.0‡
1050 1050 1050 1050 1050 1045 1040 1025 1015 1000
3---1/2---Ton A/C Cooling
1225
0---1.0‡
1225 1225 1225 1225 1225 1225 1225 1225 1185 1140
Maximum
1400
0---1.0‡
1400 1400 1400 1400 1375 1325 1280 1235 1190 1145
080---20***
††
Low Heat
880†
0---0.50
880
880
880
875
880
High Heat
1500†
0---1.0
1485 1495 1500 1500 1500 1500 1500 1485 1475 1465
††
2---Ton A/C Cooling
700
0---0.50‡
670
640
635
630
630
††
2---1/2---Ton A/C Cooling
875
0---0.50‡
870
875
865
865
865
3---Ton A/C Cooling
1050
0---1.0‡
1050 1045 1040 1045 1045 1050 1050 1050 1045 1040
3---1/2---Ton A/C Cooling
1225
0---1.0‡
1225 1225 1225 1225 1225 1225 1225 1225 1225 1225
4---Ton A/C Cooling
1400
0---1.0‡
1330 1345 1360 1375 1380 1380 1380 1370 1365 1355
5---Ton A/C Cooling
1750
0---1.0
1750 1750 1750 1750 1750 1750 1745 1725 1700 1685
Maximum
2000
0---1.0
2000 2000 2000 2000 1975 1955 1920 1870 1820 1770
100---20***
††
Low Heat
1110†
0---0.50
1105 1110 1110 1110 1110 1110 1110 1110 1110 1110
High Heat
1525†
0---1.0
1525 1525 1525 1525 1525 1525 1525 1510 1495 1470
††
2---Ton A/C Cooling
700
0---0.50‡
700
690
690
690
690
††
2---1/2---Ton A/C Cooling
875
0---0.50‡
835
845
855
860
865
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‡
1170 1190 1205 1220 1225 1225 1225 1225 1225 1225
4---Ton A/C Cooling
1400
0---1.0‡
1400 1400 1400 1400 1400 1400 1400 1400 1400 1375
5---Ton A/C Cooling
1750
0---1.0
1735 1740 1735 1735 1725 1720 1710 1695 1680 1660
Maximum
2000
0---1.0
1995 1985 1980 1965 1950 1935 1910 1885 1860 1815
120---20
Low Heat
1330†
0---1.0
1325 1330 1330 1330 1330 1330 1330 1330 1330 1325
High Heat
1900†
0---1.0
1900 1900 1900 1900 1900 1885 1875 1860 1840 1815
††
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‡
870
875
875
865
870
3---Ton A/C Cooling
1050
0---1.0‡
1025 1035 1045 1050 1050 1050 1050 1050 1040 1025
3---1/2---Ton A/C Cooling
1225
0---1.0‡
1210 1210 1210 1225 1225 1225 1225 1225 1225 1225
4---Ton A/C Cooling
1400
0---1.0‡
1385 1400 1400 1400 1400 1400 1400 1395 1375 1370
5---Ton A/C Cooling
1750
0---1.0‡
1745 1730 1735 1735 1740 1735 1730 1725 1710 1685
6---Ton A/C Cooling
2100
0---1.0
2100 2100 2080 2065 2060 2045 2030 2000 1960 1895
Maximum
2100
0---1.0
2100 2100 2080 2065 2060 2045 2030 2000 1960 1895
* 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 880 CFM at 0.13 ESP.
{
All heating CFMs are when low---heat rise adjustment switch (SW1---3) and comfort/efficiency adjustment switch (SW1---4) 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% less on side return only installations.
58U
VB