Bryant 580G III. Evaporator FAN Service and Replacement, IV. EVAPORATOR-FAN Motor Replacement

B. Fan Shaft Bearings

Lubricate the bearings at least twice annually with suitable bearing grease. Do not over grease. Typical lubricants are shown below:

MANUFACTURER	LUBRICANT
Texaco	Regal AFB-2*
Mobil	Mobilplex EP No. 1
Sunoco	Prestige 42
Texaco	Multifak 2

*Preferred lubricant because it contains rust and oxidation inhibitors.

C. Condenser and Evaporator-Fan Motor Bearings

The condenser and evaporator-fan motors have permanently- sealed bearings, so no ®eld lubrication is necessary.

III.EVAPORATOR FAN SERVICE AND REPLACEMENT

1.Turn off unit power.

2.Remove supply-air section panels.

3.Remove belt and blower pulley.

4.Loosen setscrews in blower wheels.

5.Remove locking collars from bearings.

6.Remove shaft.

7.Remove venturi on opposite side of bearing.

8.Lift out wheel.

9.Reverse above procedure to reinstall fan.

10.Check and adjust belt tension as necessary.

IV. EVAPORATOR-FAN MOTOR REPLACEMENT

1.Shut off unit power supply.

2.Remove upper outside panel and open hinged door to gain access to motor.

3.Fully retract motor plate adjusting bolts.

4.Loosen the 2 rear (nearest the evaporator coil) motor plate nuts.

5.Remove the 2 front motor plate nuts and carriage bolts.

6.Slide motor plate to the rear (toward the coil) and remove fan belt(s).

7.Slide motor plate to the front and hand tighten one of the rear motor plate nuts (tight enough to prevent the motor plate from sliding back but loose enough to al- low the plate to pivot upward).

8.Pivot the front of the motor plate upward enough to allow access to the motor mounting hex bolts and secure in place by inserting a prop.

9.Remove the nuts from the motor mounting hex bolts and remove motor.

10.Reverse above steps to install new motor.

V. POWER FAILURE

Dampers have a spring return. In event of power failure, damp- ers will return to fully closed position until power is restored.

VI. REFRIGERANT CHARGE

Amount of refrigerant charge is listed on unit nameplate and in Table 1. Refer to GTAC II; Module 5; Charging, Recovery, Recycling, and Reclamation section for charging methods and procedures.

Unit panels must be in place when unit is operating during charging procedure.

A. No Charge

Use standard evacuating techniques. After evacuating sys- tem, weigh in the speci®ed amount of refrigerant (refer to Table 1).

B. Low Charge Cooling

Using appropriate cooling charging chart (see Fig. 43), add or remove refrigerant until conditions of the appropriate chart are met. Note that charging chart is different from those normally used. An accurate pressure gage and temperature sensing device are required. Measure liquid line pressure at the liquid line service valve using pressure gage. Connect temperature sensing device to liquid line near the liquid line service valve and insulate it so that outdoor ambient tem- perature does not affect reading. Indoor-air cfm must be within normal operating range of unit. Take outdoor ambient tem- perature and read the suction pressure gage. Refer to appro- priate chart to determine correct suction temperature. If intersection point on chart is above the curve, add refrig- erant. If intersection point on chart is below curve, carefully recover some of the charge. Recheck suction pressure as charge is adjusted.

Fig. 43 Ð Cooling Charging Chart,

580G,H240-360

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