Bryant 580F Gas Valve B.Cleaning and Adjustment, Xi. Filter Drier, Xiii. Relief Devices

2 LEADS, #18 WIRE 1/32 INSULATION,	REGULATOR
600V. MAX., 105°C	ADJUSTMENT SCREW
	(REMOVE COVER)

OUTLET PRESSURE TAP (PLUGGED) 1/8-27 N.P.T. THDS.

	D-1		D-2	RECEPTACLE AND
ON				TAB COMBINATION
	W-1		C1
				TERMINAL
OFF			C2
	PILOT ADJ.	W-2		PILOT CONNECTION
INLET PRESSURE TAP				FOR 1/4” O.D. TUBING
				(PLUGGED)
(PLUGGED)
1/8 - 27 N.P.T. THDS.	RECEPTACLE TERMINAL

Fig. 43 — Gas Valve

B.Cleaning and Adjustment

1.Remove burner rack from unit as described in Main Burner Removal section on page 37.

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

3.Using a soft brush, clean burners and crossover port as required.

4.Adjust spark gap. See Fig. 44.

5.Reinstall burners on rack.

6.Reinstall burner rack as described above.

XI. FILTER DRIER

Replace whenever refrigerant system is exposed to atmosphere.

XII. PROTECTIVE DEVICES

A. Compressor Protection

Overcurrent

Each compressor has internal line break motor protection.

Crankcase Heater

All units are equipped with a 70-watt crankcase heater to prevent absorption of liquid refrigerant by oil in the crank- case when the compressor is idle. The crankcase heater is energized whenever there is main power to the unit and the compressor is not energized.

IMPORTANT: After prolonged shutdown or servicing, ener- gize the crankcase heaters for 24 hours before starting the compressors.

Compressor Lockout

If any of the safeties (high-pressure, low-pressure, freeze protection thermostat, compressor internal thermostat) trip, or if there is loss of power to the compressors, the cooling lockout (CLO) will lock the compressors off. To reset, manu- ally move the thermostat setting.

B. Evaporator Fan Motor Protection

A manual reset, calibrated trip, magnetic circuit breaker protects against overcurrent. Do not bypass connections or

increase the size of the breaker to correct trouble. Determine the cause and correct it before resetting the breaker.

C. Condenser-Fan Motor Protection

Each condenser-fan motor is internally protected against overtemperature.

D. High and Low-Pressure Switches

If either switch trips, or if the compressor overtemperature switch activates, that refrigerant circuit will be automati- cally locked out by the CLO. To reset, manually move the thermostat setting.

E. Freeze Protection Thermostat (FPT)

An FPT is located on the top and bottom of the evaporator coil. They detect frost build-up and turn off the compressor, allowing the coil to clear. Once the frost has melted, the compressor can be reenergized by resetting the compressor lockout.

XIII. RELIEF DEVICES

All units have relief devices to protect against damage from excessive pressures (i.e., fire). These devices protect the high and low side.

XIV. CONTROL CIRCUIT, 24-V

This control circuit is protected against overcurrent by a

3.2amp circuit breaker. Breaker can be reset. If it trips, determine cause of trouble before resetting. See Fig. 45 and 46 for typical wiring diagrams.

XV. REPLACEMENT PARTS

A complete list of replacement parts may be obtained from any Bryant distributor upon request.

XVI. DIAGNOSTIC IGC CONTROL LEDs

The unit control boards have LEDs for diagnostic purposes. Refer to Troubleshooting section on page 43.

XVII. OPTIONAL HINGED ACCESS DOORS

When the optional hinged access doors option is ordered, the unit will be provided with external and internal hinged access doors to facilitate service.

Four external hinged access doors are provided on size 180- 240 units. Two external hinged doors are provided on size 300 units. All external doors are provided with 2 large 1/4 turn latches with folding bail-type handles. (Compressor access doors have one latch.) A single door is provided for filter and drive access. One door is provided for control box access. The control box access door is interlocked with the non-fused disconnect which must be in the OFF position to open the door. Two doors are provided on 580F180-240 units for access to the compressor compartment.

Two internal access doors are provided inside the filter/drive access door. The filter access door (on the left) is secured by

2small 1/4 turn latches with folding bail-type handles. This door must be opened prior to opening the drive access door. The drive access door is shipped with 2 sheet metal screws holding the door closed. Upon initial opening of the door, these screws may be removed and discarded. The door is then held shut by the filter access door, which closes over it.

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