Carrier NP034-074 specifications Lubrication, Modulating Power Exhaust Damper Motor

NOTE: Only the heater element contactors are located in the heater box. The heaters are located in the unit airstream.

25% OUTDOOR-AIR DAMPER Ð Access to adjust the damper is through the hoods. Remove ®lters to gain access into unit to adjust linkage arms.

MODULATING POWER EXHAUST DAMPER MOTOR

ÐThe modulating power exhaust damper motor is located in the return-air end of the unit.

On unit sizes 034 and 044, it is accessed by removing the access panel on the left-hand corner post. See Fig. 35.

IMPORTANT: When replacing panel, be sure to prop- erly secure it in order to prevent water from being drawn into the unit.

On unit sizes 054-074, the motor is accessed through the small door below the side economizer hoods on the left side of the unit. See Fig. 36.

RETURN-AIR FILTERS Ð Access to these ®lters is through the door marked FILTER SECTION. Filters in upper and lower bag ®lter tracks can only be removed from the left side of the unit (when facing condenser end).

CONDENSER FANS AND FAN MOTORS Ð Remove the wire fan guard on top of the unit to gain access to the con- denser fans and motors.

INLET GUIDE VANE MOTOR Ð The inlet guide vane mo- tor is located on the evaporator-fan sled on the side opposite the fan motor. See Fig. 43. Access is through the door la- beled FAN SECTION on the left side of the unit.

LEGEND

CÐ Contactor

FB	Ð Fuse Block
FU	Ð Fuse
HC	Ð Heat Element Contactor
HTB Ð Heater Terminal Block
PL	Ð Plug Assembly

Fig. 42 Ð Typical Electric Heat Control Box

Cleaning Ð Inspect unit at the beginning of each heating and cooling season and during each season as operating con- ditions may require.

Clean condenser coil with a vacuum cleaner, fresh water, compressed air, or a bristle brush (not wire). Coil cleaning should be a part of the planned maintenance program. Clean evaporator coil with a stiff bristle brush (not wire), vacuum cleaner, or compressed air.

Check and clean condensate drain annually at the start of the cooling season.

Replace return-air ®lters at the start of each heating and cooling season or as often as necessary during each season, depending on operating conditions. See Tables 1A and 1B for ®lter types, quantities, and sizes.

1.Remove economizer outdoor-air ®lters from the hoods by removing the ®lter retainers.

2.Clean ®lters with steam or hot water and mild detergent.

3.Reinstall ®lters in hoods after cleaning. Never replace clean- able ®lters with throwaway ®lters.

Lubrication

COMPRESSORS Ð Each compressor is correctly charged at the factory. Refer to 06D and 06E Compressor Service Manuals if additional information regarding compressor lu- brication system is required. See Compressor Oil section on page 38 and Table 8.

FAN SHAFT BEARINGS Ð Lubricate fan shaft bearings at least once a year with suitable bearing grease. Extended grease lines are provided on pulley side of blower. Typical lubri- cants 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.

INLET GUIDE VANE BEARINGS (Units With Optional Inlet Guide Vanes) Ð These bearings are oil impregnated. Lubricate annually with a few drops of nondetergent SAE 20 oil.

FAN MOTOR BEARINGS Ð The condenser- and evaporator- fan motors have sealed bearings so no ®eld lubrication is required.

DOOR HINGES Ð All door hinges should be lubricated at least once a year.

Fig. 43 Ð Inlet Guide Vane Motor

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