Carrier 50EK, 50EJ, 50EW, 50EY Lubrication, Evaporator Fan Service and Replacement, and Adjustment

Cleaning Ð Inspect unit interior at beginning of each heat- ing and cooling season and as operating conditions require. Remove unit top panel and/or side panels for access to unit interior.

EVAPORATOR COIL Ð Clean as required with a commer- cial coil cleaner.

CONDENSER COIL Ð Clean condenser coil annually and as required by location and outdoor-air conditions. Inspect coil monthly Ð clean as required.

CONDENSATE DRAIN Ð Check and clean each year at start of cooling season. In winter, keep drains and traps dry.

FILTERS Ð Clean or replace at start of each heating and cooling season, or more often if operating conditions re- quire. Refer to Table 1 for type and size.

NOTE: The unit requires industrial grade throwaway ®lters capable of withstanding face velocities up to 625 fpm.

OUTDOOR-AIR INLET SCREENS Ð Clean screens with steam or hot water and a mild detergent. Do not use throw- away ®lters in place of screens.

Lubrication

COMPRESSORS Ð Each compressor is charged with the correct amount of oil at the factory. The correct oil charge is shown in Table 1. If oil is visible in the compressor sight glass, check unit for operating readiness as described in Start-Up section, then start the unit. Observe oil level and add oil, if required, to bring oil level in compressor crankcase up to between 1¤4 and 1¤3 of sight glass during steady operation.

If oil charge is above 1¤3 sight glass, do not remove any oil until the compressor crankcase heater has been energized for at least 24 hours with compressor off.

When additional oil or a complete charge is required, use only Carrier-approved compressor oil:

Petroleum Specialties, Inc. . . . . . . . . . . . . . . . . . Cryol 150 Texaco, Inc. . . . . . . . . . . . . . . . . . . . . . . . . . Capella WF-32 Witco Chemical Corp. . . . . . . . . . . . . . . . . . . . Suniso 3GS

IMPORTANT: Do not use reclaimed oil or oil that has been exposed to the atmosphere. Refer to Carrier Stand- ard Service Techniques Manual, Chapter 1, Refriger- ants section, for procedures to add or remove oil.

FAN SHAFT BEARINGS Ð Lubricate the bearings at least twice annually with suitable bearing grease. Do not over grease. Typical lubricants are show 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 BEAR- INGS Ð The condenser and evaporator-fan motors have permanently-sealed bearings, so no ®eld lubrication is necessary.

Evaporator Fan Performance Adjustment (Fig. 38) Ð Fan motor pulleys are factory set for speed shown in Table 1 (factory speed setting).

To change fan speeds, change pulleys. To align fan and motor pulleys:

1.Shut off unit power supply.

2.Loosen fan shaft pulley bushing.

3.Slide fan pulley along fan shaft.

4.Make angular alignment by loosening motor from mount- ing plate.

5.Retighten pulley.

IMPORTANT: Check to ensure that the unit drive matches the duct static pressure in Tables 12 to 14.

Evaporator Fan Service and Replacement

1.Turn off unit power.

2.Remove supply-air section panels.

3.Remove belt and blower pulley.

4.Loosen set screws 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.

Fig. 38 Ð Evaporator-Fan Pulley Alignment

and Adjustment

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