Bryant 830CA, Installation, Start--Up, Operating, And Service And Maintenance

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BASED ON 350 CFM/TON (SETUP SWITCH SW1---5 OFF, SW4---3 OFF)
Model Size
SETUP SWITCH SW2 OR SW3 POSITIONS
3T-040 DEF 525
2
700 875 1050 1225
1
1400 1400
4T-060 DEF 525
2
700 875 1050 1225 1400
1
1400
5T-080 DEF 700
2
875 1050 1225 1400 1750
1
2100
5T-100 DEF 700
2
875 1050 1225 1400 1750
1
2100
BASED ON 400 CFM/TON (SETUP SWITCH SW1---5 ON, SW4---3 OFF)
Model Size
SETUP SWITCH SW2 OR SW3 POSITIONS
3T-040 DEF 600
2
800 1000 1200 1400
1
1400 1400
4T-060 DEF 600
2
800 1000 1200 1400 1600
1
1600
5T-080 DEF 800
2
1000 1200 1400 1600 2000
1
2200
5T-100 DEF 800
2
1000 1200 1400 1600 2000
1
2200
BASED ON 325 CFM/TON (SETUP SWITCH SW1---5 OFF, SW4---3 ON)
Model Size
SETUP SWITCH SW2 OR SW3 POSITIONS
3T-040 DEF 488
2
650 813 975 1138
1
1300 1300
4T-060 DEF 488
2
650 813 975 1138 1300
1
1300
5T-080 DEF 650
2
813 975 1138 1300 1625
1
1950
5T-100 DEF 650
2
813 975 1138 1300 1625
1
1950
BASED ON 370 CFM/TON (SETUP SWITCH SW1---5 ON, SW4---3 ON)
Model Size
SETUP SWITCH SW2 OR SW3 POSITIONS
3T-040 DEF 558
2
744 930 1116 1302
1
1400 1400
4T-060 DEF 558
2
744 930 1116 1302 1488
1
1488
5T-080 DEF 744
2
930 1116 1302 1488 1860
1
2200
5T-100 DEF 744
2
930 1116 1302 1488 1860
1
2200
(1.) Default A/C airflow when A/C switches are in OFF position
(2.) Default continuous fan airflow when CF switches are in OFF position
(3.) Switch positions are also shown on furnace wiring diagram
Fig. 42 -- Cooling (A/C) or Continuous Fan Airflow Selection Chart
Check Safety Controls
1. Check Main Limit Switch(es)
This control shuts off combustion control system and en-
ergizes air--circulating blower motor, if furnace overheats.
By using this method to check limit control, it can be es-
tablished that limit is functioning properly and will operate
if there is a restricted duct system or motor failure. If limit
control does not function during this test, cause must be
determined and corrected.
a. Run furnace for at least 5 minutes.
b. Gradually block off return air with a piece of cardboard
or sheet metal until the limit trips.
c. Unblock return air to permit normal circulation.
d. Burners will re--light when furnace cools down.
2. Check draft safeguard switch.
The purpose of this control is to cause the safe shutdown
of the furnace during certain blocked vent conditions.
a. Verify vent pipe is cool to the touch.
b. Disconnect power to furnace and remove vent connec-
tor from furnace vent elbow.
c. Restore power to furnace and set room thermostat
above room temperature.
d. After normal start--up, allow furnace to operate for 2
minutes, then block vent elbow in furnace 80 percent
of vent area with a piece of flat sheet metal.
e. Furnace should cycle off within 2 minutes. If gas does
not shut off within 2 minutes, determine reason draft
safeguard switch did not function properly and correct
condition.
f. Remove blockage from furnace vent elbow.
g. Switch will auto--reset when it cools.
h. Re--install vent connector.