6
AIR DELIVERY -- CFM (BOTTOM RETURN WITH FILTER) (CONTINUED)
(SW1-5 and SW4-3 set to OFF, except as indicated. See Notes 1 and 2.)
INPUT
BTUH
Cooling Switch Settings
External Static Pressure (E.S.P.)
SW2-3
SW2-2
SW2-1
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
100000
OFF
OFF
OFF
2115
2035
1965
1890
1805
1725
1625
1540
1435
1345
OFF
OFF
ON
870
715
585
525
450
OFF
ON
OFF
1025
950
900
835
770
OFF
ON
ON
1210
1165
1105
1055
1000
950
895
845
800
735
ON
OFF
OFF
1400
1355
1295
1250
1205
1155
1110
1060
1020
960
ON
OFF
ON
1615
1570
1525
1485
1435
1395
1345
1310
1260
1210
ON
ON
OFF
2115
2035
1965
1890
1805
1725
1625
1540
1435
1345
ON
ON
ON
2115
2035
1965
1890
1805
1725
1625
1540
1435
1345
Maximum Cooling Airflow
2
2115
2035
1965
1890
1805
1725
1625
1540
1435
1345
High Heat Airflow
3
2115
2035
1965
1890
1805
1725
1625
1540
1435
1345
Low Heat Airflow
3
1575
1530
1485
1445
1395
1350
1305
1265
1215
1165
INPUT
BTUH
Cooling Switch Settings
External Static Pressure (E.S.P.)
SW2-3
SW2-2
SW2-1
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
120000
6
OFF
OFF
OFF
2010
1960
1910
1850
1800
1750
1690
1645
1565
1480
OFF
OFF
ON
1015
805
645
550
480
OFF
ON
OFF
1075
975
915
835
765
OFF
ON
ON
1205
1135
1055
1000
935
ON
OFF
OFF
1400
1330
1260
1190
1145
1080
1035
970
905
845
ON
OFF
ON
1615
1550
1500
1435
1370
1325
1265
1215
1160
1110
ON
ON
OFF
2010
1960
1910
1850
1800
1750
1690
1645
1565
1480
ON
ON
ON
note 7
2375
2300
2205
2115
2010
1890
1750
1645
1550
Maximum Cooling Airflow
2
note 7
2375
2300
2205
2115
2010
1890
1750
1645
1550
High Heat Airflow
3
note 7
2375
2300
2205
2115
2010
1890
1750
1645
1550
Low Heat Airflow
3
1735
1675
1625
1560
1500
1455
1395
1345
1285
1225
1. Nominal 350 CFM/ton cooling airflow is delivered with SW1-5 and SW4-3 set to OFF.
Set both SW1-5 and SW4-3 to ON for +7% airflow (nominal 370 CFM/ton).
Set SW1-5 to ON and SW4-3 to OFF for +15% airflow (nominal 400 CFM/ton).
Set SW4-3 to ON and SW1-5 to OFF for -7% airflow (nominal 325 CFM/ton).
2. Maximum cooling airflow is achieved when switches SW3-1, SW3-2, SW3-3 and SW1-5 are set to ON, and SW4-3 is set to OFF.
3.
All heating CFM's are when low heat rise adjustment switch (SW1-3) and comfort/efficiency adjustment switch (SW1-4) are both set to OFF.
4.
Ductwork must be sized for high-heating CFM within the operational range of E.S.P. Operation within the blank areas of the chart is not recommended
because high-heat operation will be above 1.0 E.S.P.
5.
All airflows on 21" (533 mm) casing size furnaces are 5% less on side return only installations.
6.
Side returns for 24.5" (622 mm) casing sizes require two sides, or side and bottom, to allow sufficient airflow at the return of the furnace.
7.
Airflow not stable at this E.S.P.