Bryant 315AAV Electrical Controls and Wiring, Component Self-Test, Electrical Shock Hazard

the furnace, and conditioned air is discharged upward. Since this furnace can be installed in any of the 4 positions shown in Fig. 4, you must revise your orientation to component location accordingly.

Electrical Controls and Wiring

!WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury or death.

There may be more than one electrical supply to the furnace. Check accessories and cooling unit for additional electrical supplies that must be shut off during furnace servicing. Lock out and tag switch with a suitable warning label.

The electrical ground and polarity for 115-v wiring must be properly maintained. Refer to Fig. 25 for field wiring information and to Fig. 53 for furnace wiring information.

NOTE: If the polarity is not correct, the STATUS LED on the control will flash rapidly and prevent the furnace from heating. The control system also requires an earth ground for proper operation of the control and flame-sensing electrode.

The 24-v circuit contains an automotive-type, 3-amp. fuse located on the control. (See Fig. 26.) Any shorts of the 24-v wiring during installation, service, or maintenance will cause this fuse to blow. If fuse replacement is required, use ONLY a 3-amp. fuse. The control LED will display status code 24 when fuse needs to be replaced.

Proper instrumentation is required to service electrical controls. The control in this furnace is equipped with a Status Code LED (Light-Emitting Diode) to aid in installation, servicing, and troubleshooting. Status codes can be viewed at the sight glass in blower access door. The amber furnace control LED is either ON continuously, rapid flashing, or a code composed of 2 digits. The first digit is the number of short flashes, the second digit is the number of long flashes.

For an explanation of status codes, refer to service label located on blower access door or Fig. 52, and the troubleshooting guide which can be obtained from your distributor.

See Fig. 58, a brief Troubleshooting Guide.

For 2-Stage Variable Speed ECM Controls the stored status codes will NOT be erased from the control memory, when 115- or 24-v power is interrupted. The control will store up to the last 7 Status Codes in order of occurrence.

1.To retrieve status codes, proceed with the following: NOTE: NO thermostat signal may be present at control, and all blower-OFF delays must be completed.

a.Leave 115-v power to furnace turned on.

b.Remove outer access door.

c.Look into blower access door sight glass for current LED status.

d.Remove blower access door.

NOTE: The Status Codes cannot be retrieved by disconnecting the limit switch or draft safeguard switch. To retrieve Status Codes, follow the procedure below.

2.Turn Setup Switch, SW1-1 “ON.”

3.Manually close blower access door switch.

4.Control will flash up to 7 Status Codes.

5.The last Status Code, or 8th Code, will be Code 11.

6.Turn SW1-1 “OFF.”

7.A continuously-lit Amber LED will appear and indicates proper operation.

8.Release blower access door switch, install blower access door and replace outer door or refer to the SERVICE label on the front of the blower access door for more informa- tion.

Component Self-Test

Component Test can ONLY be initiated by performing the following:

1.Remove outer access door.

2.Remove blower access door.

3.Remove the wire from the “R” terminal of the control board.

4.Turn Setup Switch, SW-1-6 “ON.”

5.Manually close blower access door switch.

Blower access door switch opens 115-v power to control. No component operation can occur unless switch is closed. Caution must be taken when manually closing this switch for service purposes.

!WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury, or death.

Blower access door switch opens 115-v power to furnace control. No component operation can occur unless switch is closed. Exercise caution to avoid electrical shock from exposed electrical components when manually closing this switch for service purposes.

6.Component Test sequence will function as follows:

a.Inducer motor starts on high-speed and continues to run until Step (d.) of component test sequence.

b.Hot surface igniter is energized for 15 sec, then deen- ergized.

c.Blower operates for 10 sec, then turns off.

d.Inducer motor goes to low-speed for 10 seconds, then turns off.

e.After component test is completed, one or more status codes (11, 25, or 41) will flash. See component test section of service label for explanation of status codes.

NOTE: To repeat component test, turn setup switch SW1-6 OFF then back ON.

f. Turn setup switch SW1-6 OFF.

315AAV

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