Bryant Evaporator-FanPulley and Adjustment, 580F180-300 Evaporator-FanMotor Section

Fig. 38 — Evaporator-Fan Pulley and Adjustment

NOTE: A 31/2-in. bolt and threaded plate are included in the installer’s packet. They should be added to the motor support channel below the motor mounting plate to aid in raising the motor. The plate part number is 50DP503842. The adjustment bolt is 3/8-16 x 13/4-in. LG.

Fig. 39 — 580F180-300 Evaporator-Fan Motor Section

5.Remove the belt drive.

6.Remove jacking bolt and tapped jacking bolt plate.

7.Remove the 2 screws that secure the motor mounting plate to the motor support channel.

8.Remove the 3 screws from the end of the motor sup- port channel that interfere with the motor slide path.

9.Slide out the motor and motor mounting plate.

10. Disconnect wiring connections and remove the

4 mounting bolts.

11.Remove the motor.

12.To install the new motor, reverse Steps 1-11.

V. BELT TENSION ADJUSTMENT

To adjust belt tension:

1.Loosen fan motor bolts.

2.Turn motor jacking bolt to move motor mounting plate up or down for proper belt tension (3/8 in. deflec- tion at midspan with one finger [9 lb force]).

3.Tighten nuts.

4.Adjust bolts and nut on mounting plate to secure motor in fixed position.

VI. CONDENSER-FAN ADJUSTMENT

A.580F180, 210, 300 UNITS (Fig. 40)

1.Shut off unit power supply.

2.Remove access panel(s) closest to the fan to be adjusted.

3.Loosen fan hub setscrews.

4.Adjust fan height on shaft using a straightedge placed across the fan orifice.

5.Tighten setscrews and replace panel(s).

6.Turn on unit power.

B.580F240 Units (Fig. 41)

1.Shut off unit power supply.

2.Remove fan top-grille assembly and loosen fan hub screws.

3.Adjust fan height on unit, using a straightedge placed across the fan orifice.

4.Tighten setscrews and replace rubber hubcap to pre- vent hub from rusting to motor shaft.

5.Fill hub recess with permagum if rubber hubcap is missing.

VII. POWER FAILURE

Dampers have a spring return. In event of power failure, dampers will return to fully closed position until power is restored. Do not manually operate economizer motor.

VIII. 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.

NOTE: Do not use recycled refrigerant as it may contain contaminants.

A. No Charge

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

B. Low Charge Cooling

Using cooling charging chart (see Fig. 42), add or remove refrigerant until conditions of the chart are met. Note that charging chart is different from those normally used. An accurate pressure gage and temperature-sensing device is required. Charging is accomplished by ensuring the proper amount of liquid subcooling. Measure liquid line pressure at the liquid line service valve using pressure gage. Connect temperature sensing device to the liquid line near the liquid line service valve and insulate it so that outdoor ambient temperature does not affect reading.

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