Bryant 581A operation manual II. Lubrication, IV. Evaporator FAN Service and Replacement

II. LUBRICATION

A. Compressors

Each compressor is charged with the correct amount of oil at the factory. Conventional white oil (Sontex 200LT) is used. White oil is compatible with 3GS oil, and 3GS oil may be used if the addition of oil is required. See compressor name- plate for original oil charge. A complete recharge should be four ounces less than the original oil charge When a com- pressor is exchanged in the field it is possible that a major portion of the oil from the replaced compressor may still be in the system. While this will not affect the reliablity of the replacement compressor, the extra oil will add rotor drag and increase power usage. To remove this excess oil, an access valve may be added to the lower portion of the suction line at the inlet of the compressor. The compressor should then be run for 10 minutes, shut down and the access valve opened until no oil flows. This should be repeated twice to make sure the proper oil level has been achieved.

B. Fan Shaft Bearings

For size 155 units, bearings are permanently lubricated. No field lubrication is required. For size 180 and 240 units, lubricate bearings at least every 6 months with suitable bearing grease. Extended grease line is provided for far side fan bearing (opposite drive side). Typical lubricants are given 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 field lubrication is necessary.

III.EVAPORATOR FAN PERFORMANCE ADJUSTMENT (Fig. 30-32)

Fan motor pulleys are factory set for speed shown in Table 1.

To change fan speeds:

1.Shut off unit power supply.

2.Size 155 only:

Loosen belt by loosening carriage nuts holding motor mount assembly to fan scroll side plates (A and B).

Size 180, 240 only:

Loosen nuts on the 2 carriage bolts in the mounting base. Install jacking bolt and plateunder motor base (bolt and plate are shipped in installer’s packet). Using bolt and plate, raise motor to top of slide and remove belt. Secure motor in this position by tighten- ing the nuts on the carriage bolts.

3.Loosen movable-pulley flange setscrew (see Fig. 30).

4.Screw movable flange toward fixed flange to increase speed and away from fixed flange to decrease speed. Increasing fan speed increases load on motor. Do not exceed maximum speed specified in Table 1.

See Table 11 for air quantity limits.

5.Set movable flange at nearest keyway of pulley hub and tighten setscrew. (See Table 1 for speed change for each full turn of pulley flange.)

6.Replace and tighten belts (see Belt Tension Adjust- ment section on page 27).

To align fan and motor pulleys:

1. Loosen fan pulley setscrews.

2.Slide fan pulley along fan shaft.

3.Make angular alignment by loosening motor from mounting plate.

IV. EVAPORATOR FAN SERVICE AND REPLACEMENT

A. 581A155 Units (See Fig. 31)

NOTE: To remove belts only, follow Steps 1-6.

1.Remove filter and supply-air section panels.

2.Remove unit top panel.

3.Loosen carriage nuts A and B holding motor mount assembly to fan scroll side plates.

4.Loosen screw C.

5.Rotate motor mount assembly (with motor attached) as far as possible away from evaporator coil.

6.Remove belt.

7.Rotate motor mount assembly back past original position toward evaporator coil.

8.Remove motor mounting nuts D and E (both sides).

9.Lift motor up through top of unit.

10.Reverse above procedure to reinstall motor.

11.Check and adjust belt tension as necessary.

B. 581A180 and 240 Units (See Fig. 32)

The 581A180 and 240 units use a fan motor mounting sys- tem that features a slide-out motor mounting plate. To replace or service the motor, slide out the bracket.

1.Remove the evaporator-fan access panel and the heating control access panel.

2.Remove the center post (located between the evapora- tor fan and heating control access panels) and all screws securing it.

3.Loosen nuts on the 2 carriage bolts in the motor mounting base.

4.Using jacking bolt under motor base, raise motor to top of slide and remove belt. Secure motor in this position by tightening the nuts on the carriage bolts.

5.Remove the belt drive.

Fig. 30 — Evaporator-Fan Alignment and Adjustment

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