Carrier 50TFQ004 Installation, Start-Up And Service Instructions Manual page 46

Fig. 44 — Cleaning Outdoor Coil
Fig. 45 — Propping Up Top Panel
Fig. 46 — Separating Coil Sections
UNIT 50TFQ
004-006 AND
007 (208/230 v)
007
(460 v and 575 v)
Fig. 47 — Outdoor-Fan Adjustment
Loss-of-Charge Switch —
uid line is a low-pressure switch which functions as a loss-of-
charge switch. This switch contains a Schrader core depressor.
This switch opens at 7 psig and closes at 22 psig. No adjust-
ment is necessary. Refer to Table 1.
Freezestat —
Located on the "hair pin" end of the indoor
coil is a bimetal temperature sensing switch. This switch pro-
tects the indoor coil from freeze-up due to lack of airflow. The
switch opens at 30 F and closes at 45 F. No adjustment is nec-
essary. Refer to Table 1.
Refrigerant Charge —
on the unit information plate (also refer to Table 1). Refer to
Carrier Refrigerant Service Techniques Manual, Refrigerants
section.
Unit panels must be in place when the unit is operating dur-
ing charging procedure. The unit must operate for a minimum
of 15 minutes before checking the charge.
NO CHARGE — Refer to Carrier Refrigerant Service Tech-
niques. Use standard evacuating techniques. After evacuating
the system, weigh in the specified amount of refrigerant to
500 microns. (Refer to Table 1.)
LOW CHARGE COOLING — Use Cooling Charging Charts,
Fig. 48-51. Vary refrigerant until the conditions of the charts
are met. Note that the charging charts are different from type
normally used. The charts are based on charging the units to the
correct superheat for the various operating conditions. An
accurate pressure gage and a 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 near the compressor and insulate it so that outdoor
ambient temperature does not affect the reading. Indoor-air cfm
must be within the normal operating range of the unit.
TO USE COOLING CHARGING CHARTS — Use this meth-
od in Cooling mode only. Take the outdoor ambient temperature
and read the suction pressure gage. Refer to the charging charts
to determine what the suction temperature should be. If the suc-
tion temperature is high, add refrigerant. If the suction tempera-
ture is low, carefully recover some of the charge. Recheck the
suction pressure as the charge is adjusted.
Example: (Fig. 48)
Outdoor Temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 F
Suction Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 psig
Suction Temperature should be . . . . . . . . . . . . . . . . . . . . . . 70 F
(Suction Temperature may vary ± 5° F.)
HEATING MODE CHARGE — Do not attempt to adjust the
charge by cooling methods while in Heating mode. When
charging is necessary in Heating mode, recover refrigerant and
weigh in according to the unit data plate refrigerant data.
Replacement Parts —
parts may be obtained from any Carrier distributor.
46
FAN HEIGHT — ''A''
(in.)
2.75
3.50
Located on the outdoor liq-
The refrigerant charge is listed
A complete list of replacement