Bryant 393AAV instruction manual ÐFurnace Control

BLOWER OFF DELAY ADJUSTMENT SWITCH

	G
	R
	Y
TEST/TWIN	W
	COM
	24V
	HUM

24V THERMOSTAT TERMINALS

HUMIDIFIER TERMINAL (24-VAC 0.5 AMP MAX)

LED OPERATION & STATUS LIGHT

SEC-1

3-AMP FUSE COOL

HEAT

HARNESS CONNECTOR

24V TRANSFORMER SEC-2

SPARE 1

BLOWER SPEED

SELECTION TERMINALS

SPARE 2 EAC 1 (BLACK)

	EAC-ELECTRONIC AIR CLEANER
	TERMINALS (115-VAC 1.0 AMP MAX)
115-VAC (L1)	EAC 2 (WHITE)
POWER	115-VAC (L2) NEUTRAL
SUPPLY
	CONNECTION
HOT SURFACE	INDUCER MOTOR
IGNITER	CONNECTOR
CONNECTOR
	A99258
	Fig. 6ÐFurnace Control

The 24-v circuit contains an automotive-type, 3-amp fuse located on the control. (See Fig. 6.) 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.

With power to the unit disconnected, check all electrical connec- tions for tightness. Tighten all screws on electrical connections. If any smoky or burned connections are found, disassemble the connection, clean all parts, strip wire, and reassemble properly and securely.

Reconnect electrical power to the unit and observe unit through 1 complete operating cycle. Electrical controls are difficult to check without proper instrumentation; if there are any discrepancies in the operating cycle, contact your dealer and request service.

The control in this furnace is equipped with an LED status light to aid in installation, servicing, and troubleshooting. It can be viewed through the sight glass or window on the blower access door. The control indicates status with the LED on continuously, rapid flashing, or a code composed of 2 digits. (The first digit is the number of short flashes, the second is the number of longs flashes.)

For an explanation of status codes, refer to service label located on blower access door, Fig. 8, or the troubleshooting guide.

The control stores 1 status code (the last status code to occur) for a period of 48 hr or until the 115- or 24-v power is interrupted.

NOTE: Look into blower access door sight glass for current LED status BEFORE removing the blower access door. Removing blower access door will open blower access door switch and terminate 115-v power to control, and status code will be erased.

1. To retrieve status code, proceed with the following:

NOTE: NO thermostat signal shall be present at control, and all blower off delays must be completed.

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

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

NOTE: Leave blower access panel installed to maintain power to control to view current LED status.

c.Remove control access door.

d.BRIEFLY remove either wire from the main limit switch until LED goes out, then reconnect it.

NOTE: If wire to main limit is disconnected longer than 4 sec, main blower starts, and retrieval request is ignored.

2.When above items have been completed, the following will occur:

a.LED flashes a status code 4 times. Record this status code for further troubleshooting.

b.Inducer motor starts and continues to run the entire component test.

c.Hot surface ignitor is energized for 15 sec, then de- energized.

d.Main blower operates at heating speed for 10 sec, then turns off.

e.Main blower operates at cooling speed for 10 sec, then turns off.

f.Inducer motor stops.

Items a through e above will assist in furnace troubleshooting since all components are functionally operated except the gas valve. This procedure is also referred to as ªComponent Test.º

3.Operate furnace through 1 heat cycle to test for proper operation and check LED status.

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