Carrier 50TJ016-028 specifications Evaporator Fan Service and Replacement, Manufacturer Lubricant

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.

FAN SHAFT BEARINGS — For size 016 units, bearings are permanently lubricated. No field lubrication is required. For size 020-028 units, the bearings are of the pillow block type and have grease fittings. The bearing opposite the motor end has an extended tube line so it can be lubricated from the motor side. Lubricate the bearings twice annually.

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.

CONDENSER AND EVAPORATOR-FAN MOTOR BEARINGS — The condenser and evaporator-fan motors have permanently-sealed bearings, so no field lubrication is necessary.

Evaporator Fan Performance Adjustment (Fig. 31-33) — Fan motor pulleys are factory set for speed

shown in Table 1.

To change fan speeds:

1.Shut off unit power supply.

2.a. Size 016 Only: Loosen belt by loosening fan motor mounting plate nuts.

b.Size 020-028 Only: Loosen nuts on the 2 carriage bolts in the motor mounting base. Install jacking bolt and plate under motor base (bolt and plate are shipped in installer’s packet). See Fig. 33. Using bolt and plate, raise motor to top of slide and remove belt. Secure motor in this position by tight- ening the nuts on the carriage bolts.

3.Loosen movable-pulley flange setscrew (see Fig. 31).

4.Screw movable flange toward fixed flange to increase speed and away from fixed flange to decrease speed. In- creasing fan speed increases load on motor. Do not ex- ceed maximum speed specified in Table 1.

See Table 7 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 Adjustment section on page 26.

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.

Evaporator Fan Service and Replacement

50TJ016 UNITS (See Fig. 32)

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 as- sembly 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.

50TJ020-028 UNITS (See Fig. 33) — The 50TJ020-028 units use a fan motor mounting system 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 evaporator fan and heating control access panels) and all screws se- curing it.

3.Loosen nuts on the two carriage bolts in the motor mount- ing 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.

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 support 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 mount- ing bolts.

11.Remove the motor.

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

Fig. 31 — Evaporator-Fan Pulley Alignment

and Adjustment

25