Bryant CONDENSING GAS FURNACE 355MAV, Installation, Start-Up, And Operating Instructions Manual

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CAUTION: 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.
II. SELECT SETUP SWITCH POSITIONS
A. 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 door.
2. Locate A/C setup switches on frunace control. (See Fig.
32.)
3. Determine air conditioning tonnage used.
4. Use Fig. 50 or wiring schematic to determine proper setup
position of A/C switches. (See Fig. 31 and 51.)
NOTE:
Excessive airflow caused by improper A/C switch setup
may cause condensate blow off in cooling mode.
5. Replace main furnace door and blower access door.
NOTE: EAC-1 terminal is energized whenever blower operates.
HUM terminal is only energized when blower is energized in
heating.
B. 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 door.
2. Locate CF setup switches on furnace control. (See Fig. 32.)
3. Determine desired continuous fan airflow or low-cooling
airflow.
4. Use Fig. 58 or wiring schematic to determine proper setup
position of CF switches. (See Fig. 31 and 51.)
5. Replace main furnace door and blower access panel.
C. Setup Switches (SW1)
The furnace control has 8 setup switches that may be set to meet
the application requirements. Position these setup switches for the
appropriate requirement.
1. Remove main furnace door and blower access panel.
2. Locate setup switches on furnace control. (See Fig. 32.)
3. See Table 9 for setup switch description. (See Fig. 31 and
51.)
A02335
Fig. 50—A/C or CF Airflow Selection Chart
Based on 350CFM/Ton
AIR CONDITIONING AIRFLOW 040,060 & 042080
MODEL
060080 & 100
MODEL
120 MODEL
TONS (12,000 BTU/HR) (CFM)
1-1/2 525 X
X
2 700 X X X
2-1/2 875 X X X
3 1050 X X X
3-1/2 1225 X X X
4 1400 X X
5 1750 X
6 2100 X
X-INDICATES AN ALLOWABLE SELECTION.
A/C OR CF AIRFLOW SELECTION CHART
BASED ON 350 CFM/TON
MODEL
SIZE
040, 060,
042080
DEF 525
2
700 875 1050
1
1225 1225 1225
060080, 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
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