Charging - Lennox HSXA15 SERIES Installation Instructions Manual

Charging

This system is charged with R410A refrigerant which oper-
ates at much higher pressures than HCFC−22. The expan-
sion valve and liquid line filter drier provided with the unit
are approved for use with R410A. Do not replace them with
components designed for use with HCFC−22. This unit is
NOT approved for use with coils which include metering
orifices or capillary tubes.
Processing Procedure
Units are factory charged with the amount of R410A refrig-
erant indicated on the unit rating plate. This charge is
based on a matching indoor coil and outdoor coil with 15
feet (4.6 m) line set. For varying lengths of line set, refer to
table 3 for refrigerant charge adjustment.
Table 3
Liquid Line Set Oz. per 5 ft. (grams per 1.5m) adjust
Diameter
5/16 in
(8 mm)
3/8 in.
(10 mm)
*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.
IMPORTANT
Mineral oils are not compatible with R410A. If oil
must be added, it must be a polyol ester oil.
The compressor is charged with sufficient polyol ester
oil for line set lengths up to 50 feet (15.2 m). If oil must
be added in the field, Copeland has approved Mobil
EALt Arctic 22CC and ICI EMKARATEt RL32CF for
use with these compressors.
If the system is void of refrigerant, clean the system us-
ing the procedure described below.
1 − Use nitrogen to pressurize the system and check for
leaks. Repair leaks, if possible.
2 − Evacuate the system to remove as much of the mois-
ture as possible.
3 − Use nitrogen to break the vacuum and install the pro-
vided filter drier in the system.
4 − Evacuate the system again. Then, weigh the appropri-
ate amount of R410A refrigerant (listed on unit name-
plate) into the system.
5 − Monitor the system to determine the amount of mois-
ture remaining in the oil. Use test kit 10N46 to verify
that the moisture content is within the kit's dry color
range. It may be necessary to replace the filter drier
several times to achieve the required dryness level. If
system dryness is not verified, the compressor will
fail in the future.
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.
from 15 ft. (4.6 m) line set*
2 ounces per 5 feet
(57 g per 1.5 m)
3 ounces per 5 feet
(85 g per 1.5 m)
Measure the liquid line temperature and the outdoor ambi-
ent temperature as outlined below:
1 − Connect the manifold gauge set to the service valves:
low pressure gauge to vapor valve service port
D
D high pressure gauge to liquid valve service port
Connect the center manifold hose to an upright cylin-
der of HCFC-22. Close manifold gauge set valves.
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 68_F
(20_C). 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 Fixed Orifice or
TXV Systems – Outdoor Temp < 65_F (18_C)
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.
Charging Using Normal Operating Pressures
and the Approach Method
TXV Systems – Outdoor Temp. > 65_F (18_C)
The following procedure is intended as a general guide and
is for use on expansion valve systems only. For best results,
indoor temperature should be 70°F (21°C) to 80°F (26°C).
Monitor system pressures while charging.
1 − Record outdoor ambient temperature using a digital
thermometer.
2 − Attach high pressure gauge set and operate unit for
several minutes to allow system pressures to stabilize.
3 − Compare stabilized pressures with those provided in
table 5, Normal Operating Pressures." Minor varia-
tions in these pressures may be expected due to differ-
ences in installations. Significant differences could
mean that the system is not properly charged or that a
problem exists with some component in the system.
Pressures higher than those listed indicate that the
system is overcharged. Pressures lower than those
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