Carrier 50HJQ004-007 Installation, Start-Up And Service Instructions Manual page 36

CONDENSATE DRAIN — Check and clean each year at
start of cooling season. In winter, keep drain dry or protect
against freeze-up.
FILTERS — Clean or replace at start of each heating and cool-
ing season, or more often if operating conditions require it. Re-
placement filters must be same dimensions as original filters.
OUTDOOR-AIR INLET SCREENS — Clean screens with
steam or hot water and a mild detergent. Do not use disposable
filters in place of screens.
Lubrication
COMPRESSOR — The compressor is charged with the cor-
rect amount of oil at the factory.
FAN MOTOR BEARINGS — Fan
permanently lubricated. No further lubrication of outdoor- or
indoor-fan motors is required.
High-Pressure Switch —
contains a Schrader core depressor, and is located on the com-
pressor hot gas line. This switch opens at 428 psig and closes at
320 psig. No adjustment is necessary.
Loss-of-Charge Switch —
contains a Schrader core depressor, and is located on the com-
pressor hot gas line. This switch opens at 7 psig and closes at
22 psig. No adjustment is necessary.
Freeze-Stat —
The freeze-stat is a bimetal temperature-
sensing switch that is located on the "hair pin" end of the evap-
orator coil. The switch protects the evaporator coil from freeze-
up due to lack of airflow. The switch opens at 30 F and closes
at 45 F. No adjustment is necessary.
Outdoor-Fan Adjustment (Fig. 38)
1. Shut off unit power supply and tag disconnect.
2. Remove outdoor-fan assembly (grille, motor, motor cov-
er, and fan) by removing screws and flipping assembly
onto unit top cover.
3. Loosen fan hub setscrews.
4. Adjust fan height as shown in Fig. 38.
5. Tighten setscrews.
6. Replace outdoor-fan assembly.
Blower Belt Adjustment —
wear and proper belt tension, and pulley alignment as condi-
tions require, or at the beginning of each heating and air condi-
tioning season. Refer to Step 7 — Adjust Indoor-Fan Speed on
page 19 for adjustment and alignment procedures.
Economizer Adjustment —
mizer sections on pages 12 and 14.
Refrigerant Charge —
listed on unit nameplate (also refer to Table 1). Refer to Carrier
Refrigerant Service Techniques Manual, Refrigerants section.
motor bearings
The high pressure switch
The loss-of-charge switch
Inspect blower belt for
Refer to Optional Econo-
Amount of refrigerant charge is
Unit panels must be in place when unit is operating during
charging procedure. Compressor must run a minimum of
10 minutes before checking or adjusting refrigerant charge.
NO CHARGE — Refer to Carrier Refrigerant Service Tech-
niques. Use standard evacuating techniques. After evacuating
system to 500 microns, weigh in the specified amount of refrig-
erant. (Refer to Table 1.)
CHARGING, HEATING MODE — Do not attempt to adjust
refrigerant charge while unit is operating in the Heating mode.
If refrigerant charge amount is suspect, evacuate refrigerant
system to 500 microns and weigh in refrigerant amount listed
on unit data plate.
LOW CHARGE COOLING — Use Cooling Charging Charts,
are Fig. 39-42. Vary refrigerant until the conditions of the charts
are met. Note that the charging charts are different from type
normally used. Charts are based on charging the units to the
correct superheat for the various operating conditions. Accu-
rate pressure gage and temperature sensing device are required.
Connect the pressure gage to the service port on the suction
line. Mount the temperature sensing device on the suction line
and insulate it so that outdoor ambient temperature does not af-
fect the reading. Indoor-air cfm must be within the normal op-
erating range of the unit.
NOTE: Do not use mercury or dial type pocket thermometers
as they are not designed for this type of temperature
measurement.
TO USE COOLING CHARGING CHARTS — Take the out-
door ambient temperature and read the suction pressure gage.
Refer to charts to determine what the suction temperature
should be. If suction temperature is high, add refrigerant. If
suction temperature is low, carefully recover some of the
charge. Recheck the suction pressure as charge is adjusted.
Example: (Fig. 39)
Outdoor Temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 F
Suction Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 psig
Suction Temperature should be . . . . . . . . . . . . . . . . . . . . . . 52 F
(Suction Temperature may vary ± 5° F.)
UNIT 50HJQ
004-006 AND
007 (208/230 v)
Fig. 38 — Outdoor-Fan Adjustment
36
FAN HEIGHT (in.)
2.75
007
3.50
(460 v)