33
Table 9
---
Cooling
4
and Heating Air Delivery -- CFM (Bottom Return
5
with Filter) (Con’t)
Unit Size
Cooling Switch Settings
External Static Pressure (ESP)
SW2-8
SW2-7
SW2-6
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
100--20
Clg Default:
OFF
OFF
OFF
1890
1845
1800
1755
1700
1655
1610
1560
1510
1460
Cooling (SW2)
OFF
OFF
ON
1015
825
630
485
405
325
See note 4
OFF
ON
OFF
1080
895
815
740
690
615
555
475
See note 4
OFF
ON
ON
1155
1080
1020
940
890
825
785
710
660
590
ON
OFF
OFF
1310
1260
1195
1140
1075
1025
970
925
875
810
ON
OFF
ON
1520
1475
1425
1365
1315
1255
1210
1155
1110
1055
ON
ON
OFF
1890
1845
1800
1755
1700
1655
1610
1560
1510
1460
ON
ON
ON
2290
2230
2160
2085
2005
1915
1820
1730
1640
1525
Clg SW2:
Maximum Clg Airflow
2
2290
2230
2160
2085
2005
1915
1820
1730
1640
1525
Heating
(SW1)
High Heat Airflow
3
1905
1865
1825
1775
1730
1685
1640
1590
1545
1490
Low Heat Airflow
3
1480
1435
1375
1330
1265
1215
1160
1115
1060
1005
120--22
Clg Default:
OFF
OFF
OFF
2010
1960
1910
1850
1800
1750
1690
1645
1565
1480
Cooling (SW2)
OFF
OFF
ON
1015
805
645
550
480
See note 4
OFF
ON
OFF
1075
975
915
835
765
See note 4
OFF
ON
ON
1205
1135
1055
1000
935
See note 4
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 8
2375
2300
2205
2115
2010
1890
1750
1645
1550
Clg SW2:
Maximum Clg Airflow
2
note 8
2375
2300
2205
2115
2010
1890
1750
1645
1550
Heating
(SW1)
High Heat Airflow
3
note 8
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 SW2---2 set to OFF.
Set both SW1---5 and SW2---2 to ON for +7% airflow (nominal 370 CFM/ton).
Set SW1---5 to ON and SW2---2 to OFF for +15% airflow (nominal 400 CFM/ton).
Set SW2---2 to ON and SW1---5 to OFF for ---7% airflow (nominal 325 CFM/ton).
The above adjustments in airflow are subject to motor horsepower range/capacity.
2. Maximum cooling airflow is achieved when switches SW2---6, SW2---7, SW2---8 and SW1---5 are set to ON, and SW2---2 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 ESP. Operation within the blank areas of the chart is not recommended
because high---heat operation will be above 1.0 ESP.
5. All airflows of 1880 CFM or less on 21” and 24.5” casing size furnaces are 5% less on side return only installations.
6. Return air above 1800 CFM on 24.5” casing requires two sides, one side and bottom, or bottom only to allow sufficient airflow to the furnace.
7. For upflow applications, air entering from one side into both the side of the furnace and a return air base counts as a side and bottom return.
8. Airflow not stable at this ESP.
59TP6A