Bryant 581B Flue GAS Passageways, XI. COMBUSTION-AIR Blower, XII. Limit Switch, XIV. Main Burners

E. To Use Cooling Charging Charts, Units With Perfect Humidity™ Dehumidification System

Refer to charts (Fig. 52-55) to determine the proper leaving condenser pressure and temperature.

Example (Fig. 52):

Leaving Condenser Pressure. . . . . . . . . . . . . . . . . . . .250 psig Leaving Condenser Temperature . . . . . . . . . . . . . . . . . . 105 F

NOTE: When using the charging charts, it is important that only the subcooling/reheat dehumidification coil liquid line solenoid valve be energized. The subcooling/reheat dehumid- ification coil liquid line solenoid valve MUST be energized to use the charging charts and the outdoor motor speed control- ler jumpered to run the fan at full speed.

X. FLUE GAS PASSAGEWAYS

To inspect the flue collector box and upper areas of the heat exchanger:

1.Remove the combustion blower wheel and motor assembly according to directions in Combustion-Air Blower section following.

2.Remove the 3 screws holding the blower housing to the flue cover.

3.Remove the flue cover to inspect the heat exchanger.

4.Clean all surfaces as required using a wire brush.

XI. COMBUSTION-AIR BLOWER

Clean periodically to ensure proper airflow and heating effi- ciency. Inspect blower wheel every fall and periodically during heating season. For the first heating season, inspect blower wheel bimonthly to determine proper cleaning frequency.

To inspect blower wheel, remove draft hood and screen. Shine a flashlight into opening to inspect wheel. If cleaning is required, remove motor and wheel as follows:

1.Slide burner access panel out.

2.Remove the 5 screws that attach induced-draft motor assembly to the vestibule cover.

3.Slide the motor and blower wheel assembly out of the blower housing. The blower wheel can be cleaned at this point. If additional cleaning is required, continue with Steps 4 and 5.

4.To remove blower from the motor shaft, by remove 2 setscrews.

5.To remove motor, remove the 4 screws that hold the motor to mounting plate. Remove the motor cooling fan by removing one setscrew. Then remove nuts that hold motor to mounting plate.

6.To reinstall, reverse the procedure outlined above.

XII. LIMIT SWITCH

Remove blower access panel (Fig. 7). Limit switch is located on the fan deck.

XIII. BURNER IGNITION

Unit is equipped with a direct spark ignition 100% lockout system. Integrated Gas Unit Controller (IGC) is located in the control box (Fig. 12). A single LED on the IGC provides a visual display of operational or sequential problems when the power supply is uninterrupted. The LED can be observed through the viewport. When a break in power occurs, the IGC will be reset (resulting in a loss of fault history) and the evaporator fan on/off times delay will be reset. During servic- ing, refer to the label on the control box cover or Table 31 for an explanation of LED error code descriptions.

If lockout occurs, unit may be reset by interrupting power supply to unit for at least 5 seconds.

Table 31 — LED Error Code Description*

LED INDICATION	ERROR CODE DESCRIPTION
ON	Normal Operation
OFF	Hardware Failure
1 Flash†	Evaporator Fan On/Off Delay Modified
2 Flashes	Limit Switch Fault
3 Flashes	Flame Sense Fault
4 Flashes	4 Consecutive Limit Switch Faults
5 Flashes	Ignition Lockout Fault
6 Flashes	Induced-Draft Motor Fault
7 Flashes	Rollout Switch Fault
8 Flashes	Internal Control Fault
9 Flashes	Software Lockout

LEGEND

LED — Light-Emitting Diode

*A 3-second pause exists between LED error code flashes. If more than one error code exists, all applicable codes will be displayed in numerical sequence.

†Indicates a code that is not an error. The unit will continue to operate when this code is displayed.

IMPORTANT: Refer to Troubleshooting Tables 32-36 for additional information.

XIV. MAIN BURNERS

At the beginning of each heating season, inspect for deteriora- tion or blockage due to corrosion or other causes. Observe the main burner flames and adjust, if necessary.

CAUTION: When working on gas train, do not hit or plug orifice spuds.

A. Removal and Replacement of Gas Train (See Fig. 56 and 57)

1.Shut off manual gas valve.

2.Shut off power to unit tag disconnect.

3.Remove compressor access panel.

4.Slide out burner compartment side panel.

5.Disconnect gas piping at unit gas valve.

6.Remove wires connected to gas valve. Mark each wire.

7.Remove induced-draft motor, ignitor, and sensor wires at the Integrated Gas Unit Controller (IGC).

8.Remove the 2 screws that attach the burner rack to the vestibule plate.

9.Remove the gas valve bracket.

10.Slide the burner tray out of the unit (Fig. 57).

11.To reinstall, reverse the procedure outlined above.

B. Cleaning and Adjustment

1.Remove burner rack from unit as described above.

2.Inspect burners and, if dirty, remove burners from rack.

3.Using a soft brush, clean burners and cross-over port as required.

4.Adjust spark gap. See Fig. 58.

5.Reinstall burners on rack.

6.Reinstall burner rack as described above.

XV. REPLACEMENT PARTS

A complete list of replacement parts may be obtained from your Bryant distributor upon request. Refer to Fig. 59 for a typical unit wiring schematic.

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