Carrier 50GJ006, Инструкция по установке, запуску и обслуживанию, Страница: 29 / 36

Lubrication
COMPRESSORS — Each compressor is charged with cor-
rect amount of oil at the factory. Never add mineral oil to
system.
FAN MOTOR BEARINGS — Fan motor bearings are per-
manently lubricated. No further lubrication of condenser- or
evaporator-fan motors is required.
Condenser Fan Adjustment (Fig. 36)
1. Shut off unit power supply.
2. Remove condenser-fan assembly (grille, motor, motor cover,
and fan) and loosen fan hub setscrews.
3. Adjust fan height as shown in Fig. 36.
4. Tighten setscrews and replace condenser-fan assembly.
Economizer Adjustment —
Refer to Optional Econo-
mizer sections on pages 13 and 16.
Refrigerant Charge —
Amount of refrigerant charge
is listed on unit nameplate (also refer to Table 1). Refer to
Carrier Standard Service Techniques Manual, Chapter 1, Re-
frigerants section. Unit must be charged with refrigerant R-407C.
R-22 cannot be used.
Unit panels must be in place when unit is operating dur-
ing charging procedure.
NO CHARGE — Use standard evacuating techniques. After
evacuating system, weigh in the specified amount of refrig-
erant (refer to Table 1). Refrigerant R-407C must be charged
in liquid state to ensure proper mixture.
LOW CHARGE COOLING — Use Cooling Charging Charts,
Fig. 37-39. Vary refrigerant until the conditions of the ap-
propriate chart are met. Note that charging charts are dif-
ferent from the type normally used. Charts are based on charging
the units to the correct superheat for the various operating
conditions. Accurate pressure gage and tem-perature sens-
ing device are required. Units charged with R-407C must
use dedicated hoses and pressure gages. Connect the pres-
sure gage to the service port on the suction line. Since liquid
must be removed from the refrigerant cylinder, it is impor-
tant to charge the refrigerant slowly into the suction line to
allow it to flash before it enters the system, in order to avoid
damage to the compressor from liquid refrigerant entering
the suction side of the compresor. A throttling device may
also be used to cause refrigerant to flash before entering sys-
tem. Mount the temperature sensing device on the suction
line and insulate it so that outdoor ambient temperature does
not affect the reading. Indoor-air cfm must be within the nor-
mal operating range of the unit.
TO USE COOLING CHARGING CHARTS — Take the out-
door ambient temperature and read the suction pressure gage.
Refer to appropriate chart to determine what the suction tem-
perature should be. If suction temperature is high, add re-
frigerant. If suction temperature is low, carefully reclaim some
of the charge. When reclaiming refrigerant, a dedicated re-
frigerant cylinder must be used for R-407C. Recheck the suc-
tion pressure as charge is adjusted.
EXAMPLE: (Fig. 37)
Circuit 1
Outdoor Temperature . . . . . . . . . . . . . . . . . . . . 85 F
Suction Pressure . . . . . . . . . . . . . . . . . . . . . 74 psig
Suction Temperature should be . . . . . . . . . . . . . 66 F
(Suction Temperature may vary
6
5° F.)
If Chargemaster
t
charging device is used, temperature and
pressure readings must be accomplished using the R-407C
charging chart.
UNIT 50GJ FAN HEIGHT -‘‘A’’ (in.)
006 AND
008,012 (208/230 v)
2.75
008,012
(460 and 575 v)
3.50
Fig. 36 — Condenser-Fan Adjustment
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