Page 9
IMPORTANT
Use a thermocouple or thermistor electronic vacuum
gauge that is calibrated in microns. Use an instrument
that reads from 50 microns to at least 10,000 microns.
1 − Connect manifold gauge set to the service valve ports :
low pressure gauge to vapor line service valve
high pressure gauge to liquid line service valve
2 − Connect micron gauge.
3 − Connect the vacuum pump (with vacuum gauge) to the
center port of the manifold gauge set.
4 − Open both manifold valves and start the vacuum
pump.
5 − Evacuate the line set and indoor unit to an absolute
pressure of 23,000 microns (29.01 inches of mercury).
During the early stages of evacuation, it is desirable to
close the manifold gauge valve at least once to deter-
mine if there is a rapid rise in absolute pressure. A rap-
id rise in pressure indicates a relatively large leak. If this
occurs, repeat the leak testing procedure.
NOTE − The term absolute pressure means the total
actual pressure within a given volume or system, above
the absolute zero of pressure. Absolute pressure in a
vacuum is equal to atmospheric pressure minus vacu-
um pressure.
6 − When the absolute pressure reaches 23,000 microns
(29.01 inches of mercury), close the manifold gauge
valves, turn off the vacuum pump and disconnect the
manifold gauge center port hose from vacuum pump.
Attach the manifold center port hose to a nitrogen cylin-
der with pressure regulator set to 150 psig (1034 kPa)
and purge the air from the hose with nitrogen. Open the
manifold gauge valves to break the vacuum in the line
set and indoor unit. Close the manifold gauge valves.
CAUTION
Danger of Equipment Damage.
Avoid deep vacuum operation. Do not use compres-
sors to evacuate a system.
Extremely low vacuums can cause internal arcing and
compressor failure.
Damage caused by deep vacuum operation will void
warranty.
7 − Shut off the nitrogen cylinder and remove the manifold
gauge hose from the cylinder. Open the manifold gauge
valves to release the nitrogen from the line set and in-
door unit.
8 − Reconnect the manifold gauge to the vacuum pump,
turn the pump on, and continue to evacuate the line set
and indoor unit until the absolute pressure does not rise
above 500 microns (29.9 inches of mercury) within a
20−minute period after shutting off the vacuum pump
and closing the manifold gauge valves.
9 − When the absolute pressure requirement above has
been met, disconnect the manifold hose from the vacu-
um pump and connect it to an upright cylinder of R−410A
refrigerant. Open the manifold gauge valves to break the
vacuum from 1 to 2 psig positive pressure in the line set
and indoor unit. Close manifold gauge valves and shut
off the R−410A cylinder and remove the manifold gauge
set.
C − Charging
NOTES −
R−410A refrigerant cylinders are rose−colored. Re-
frigerant should be added through the vapor valve
in the liquid state.
Certain R−410A cylinders are identified as being
equipped with a dip tube. These allow liquid refrig-
erant to be drawn from the bottom of the cylinder
without inverting the cylinder. DO NOT turn this type
cylinder upside−down to draw refrigerant.
TABLE 2
Approach Values
XC13
Model
−018 −024 −030 −036 −042 −048 −060
Temp.
°F (°C)
12
(6.7)
12
(6.7)
7
(4)
10
(5.5)
7
(4)
7
(4)
9
(5)
Liquid Line Temperature F (C)
Outdoor Ambient Temperature F ( C)
=
Approach Value F (C)
IMPORTANT
Use table 6 to perform maintenance checks. Table 6 is
not a procedure for charging the system. Minor varia-
tions in these pressures may be due to differences in
installations. Significant deviations could mean that
the system is not properly charged or that a problem
exists with some component in the system.
This system is charged with R−410A refrigerant which oper-
ates at much higher pressures than R−22. The installed liq-
uid line filter drier is approved for use with R−410A. Do not
replace it with components designed for use with R−22. This
unit is NOT approved for use with coils which use capillary
tubes as a refrigerant metering device.
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