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Start−Up
1 − Rotate the fan to check for frozen bearings or binding.
2 − Inspect all factory− and field-installed wiring for loose
connections.
3 − After evacuation is complete, open the liquid line and
vapor line service valves to release the refrigerant
charge (contained in outdoor unit) into the system.
4 − Replace the stem caps and secure finger tight, then
tighten an additional one-sixth (1/6) of a turn.
5 − Check voltage supply at the disconnect switch. The
voltage must be within the range listed on the unit’s
nameplate. If not, do not start the equipment until you
have consulted the power company and the voltage
condition has been corrected.
6 − Set the thermostat for a cooling demand. Turn on pow-
er to the indoor blower and close the outdoor unit dis-
connect switch to start the unit.
7 − Recheck voltage while the unit is running. Power must
be within range shown on the nameplate.
Charging
Units are factory charged with the amount of HCFC-22 re-
frigerant indicated on the unit nameplate. This charge is
based on a matching indoor coil and outdoor coil with a 15
ft. (4.6 m) line set. For varying lengths of line set, refer to
table 3 for refrigerant charge adjustment check.
Table 3
Liquid Line
Set Diameter
Oz. per 5 ft. (g per 1.5 m) adjust
from 15 ft. (4.6 m) line set*
3/8 in. (9.5 mm) 3 ounces per 5 ft. (88.05 g per 1.5 m)
*If line length is greater than 15 ft. (4.6 m), add this amount. If line length
is less than 15 ft. (4.6 m), subtract this amount
The outdoor unit should be charged during warm weather.
However, applications arise in which charging must occur
in the colder months. The method of charging is deter-
mined by the unit’s refrigerant metering device and the
outdoor ambient temperature.
Measure the liquid line temperature and the outdoor ambi-
ent temperature as outlined below. Close manifold gauge
set valves.
1 − Connect the manifold gauge set to the service valves:
low pressure gauge to vapor valve service port
high pressure gauge to liquid valve service port
Connect the center manifold hose to an upright cylin-
der of HCFC−22.
2 − Set the room thermostat to call for heat. This will create
the necessary load for properly charging the system in
the cooling cycle.
3 − Use a digital thermometer to record the outdoor ambi-
ent temperature.
4 − When the heating demand has been satisfied, switch
the thermostat to cooling mode with a set point of 68F
(20C). When pressures have stabilized, use a digital
thermometer to record the liquid line temperature.
5 − The outdoor temperature will determine which charg-
ing method to use. Proceed with the appropriate charg-
ing procedure.
Weighing in the Charge TXV Systems – Outdoor
Temp < 65F (18C)
If the system is void of refrigerant, or if the outdoor ambient
temperature is cool, the refrigerant charge should be
weighed into the unit. Do this after any leaks have been re-
paired.
1 − Recover the refrigerant from the unit.
2 − Conduct a leak check, then evacuate as previously
outlined.
3 − Weigh in the unit nameplate charge.
If weighing facilities are not available or if you are charging
the unit during warm weather, follow one of the other proce-
dures outlined below.
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