UNIT MAY NOT OPERATE
Failure to follow this caution may result in intermittent unit
operation or performance satisfaction.
These furnaces are equipped with a manual reset limit switch
in burner box. This switch opens and shuts off power to the
gas valve if an overheat condition (flame rollout) occurs in
burner enclosure. Correct inadequate combustion-air supply
or improper venting condition before resetting switch. DO
NOT jumper this switch.
Before operating furnace, check flame rollout manual reset switch
for continuity. If necessary, press button to reset switch.
Step 2—Select Setup Switch Positions
AIR CONDITIONING (A/C) SETUP SWITCHES
The air conditioning setup switches are used to match furnace
airflow to cooling unit used.
To set the desired cooling airflow:
1. Remove main furnace door and blower access panel.
2. Locate A/C setup switches on furnace control. (See Fig. 37.)
3. Determine air conditioning tonnage used.
4. Use Fig. 47 or wiring schematic to determine proper setup
position of A/C switches. (See Fig. 36 and 48.)
NOTE:
Excessive airflow caused by improper A/C switch setup
may cause condensate blowoff in cooling mode.
5. Replace main furnace door and blower access panel.
NOTE:
EAC-1 terminal is energized whenever blower operates.
HUM terminal is only energized when blower is energized in
heating.
CONTINUOUS FAN (CF) SETUP SWITCHES
The CF setup switches are used to select desired airflow when
thermostat is in continuous fan mode or to select low-cooling
airflow for two-speed cooling units. This setup feature allows
continuous fan airflow or low-cooling airflow to be adjusted. To
set desired continuous fan airflow or low-cooling airflow:
1. Remove main furnace door and blower access panel.
2. Locate CF setup switches on furnace control. (See Fig. 37.)
3. Determine desired continuous fan airflow or low-cooling
airflow.
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Fig. 47—A/C or CF Airflow Selection Chart
Based on 350 and 400CFM/Ton
AIR CONDITIONING
AIRFLOW*
040,060 & 080-14
MODEL
080-20 & 100
MODEL
120 MODEL
TONS (12,000 BTU/HR)
(CFM)
1-1/2
525 (600)
X
X
2
700 (800)
X
X
X
2-1/2
875 (1000)
X
X
X
3
1050 (1200)
X
X
X
3-1/2
1225 (1400)
X
X
X
4
1400 (1600)
X
X
5
1750 (2000)
X
6
2100 (2100)
X
X-INDICATES AN ALLOWABLE SELECTION.
A/C OR CF AIRFLOW SELECTION CHART
BASED ON 350 CFM/TON
MODEL
SIZE
040, 060,
080-14
DEF
525
2
700
875
1050
1
1225
1225
1225
080-20, 100
DEF
700
875
1050
1225
1400
1750
1
1750
120
DEF
700
875
2
1050
1225
1400
1750
1
2100
1.DEFAULT A/C AIRFLOW WHEN A/C SWITCHES ARE IN OFF POSITION
2.DEFAULT CONT. FAN AIRFLOW WHEN CF SWITCHES ARE IN OFF POSITION
2
* Airflow shown in parentheses is airflow unit that the unit will deliver when setup switch SW1-5 is ON (selects 400 CFM/ton)
Fig. 48—Example of Setup Switch in Off Position
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