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SPA Cooling
Cycle (Showing
Gauge
Manifold
Connections)
r
i
i
EXPANSION/
I
CHECK
VALVE
LOW
HIGH
PRESSURE
PRESSURE
J
DISTRIBUTOR
BIFLOW
DRIER
OUTDOOR
d
COIL
M U FLL__"-
COMPRESSOR
t
%
X
OUTDOOR UNIT
NOTE _ARROWS
INDICATE
DIRECTION
OF REFRIGERANT
FLOW
REVERSING
VALVE
_!
INDOOR_L]
I
III
NOTE - Use gauge ports on vapor line valve and liquid valve for evacuating refrigerant
lines and indoor coil. Use vapor gauge port to measure vapor pressure during charging,
Figure
17
A IMPORTANT
System is charged with R-410A refrigerant and operates at
much higher pressures
than R-22. The field-provided
check/expansion
valve for indoor unit must be approved
for use with R-410A. This unit is NOT approved for use with
coils which include metering orifices or capillary tubes,
Processing
Procedure
The unit is factory-charged with the amount of R-410A re-
frigerant indicated on the unit rating plate, This charge is
based on a matching indoor coil and outdoor coil with a 15
foot (4,6 m) line set. For varying lengths of line set, refer to
table 3 for refrigerant charge adjustment,
Table
3
Refrigerant
Charge
per Line Set Lengths
Liquid Line
Oz. per 5 ft. (g per 1.5 m) adjust
Set Diameter
from 15 ft. (4.6 m) line set*
3/8 in, (9,5 mm)
3 ounce per 5 ft, (85 g per1,5 m)
NOTE - *If line length is greater than 15 ft. (4.6 m), add this
amount; if less than 15 ft. (4.6 m), subtract this amount.
A IMPORTANT
The compressor is charged with sufficient polyol ester oil
for line set lengths up to 50 ft, 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 determined by the outdoor am-
bient temperature.
Measure the liquid line temperature
and the outdoor ambient temperature as outlined below:
1. Connect
manifold gauge set to service valves as
shown in figure 17:
• 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 R-410A. 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_%). 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
charging procedure,
Weighing
in the Charge
- Outdoor
Temperature
< 65°F (18°0)
If system is void of refrigerant, or if the outdoor ambient
temperature
is cool, the refrigerant
charge should be
weighed into the unit after any leaks are repaired:
1. Recover the refrigerant from the unit,
2. Conduct a leak check, then evacuate as previously
outlined,
3. Weigh in the unit nameplate charge.
Page 13
SPA SERIES
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