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IV − CHARGING
WARNING
R−410A refrigerant can be harmful if it is inhaled.
R−410A refrigerant must be used and recovered re-
sponsibly.
Failure to follow this warning may result in personal
injury or death.
A − Leak Testing
After the line set has been connected to the indoor and out-
door units, check the line set connections and indoor unit
for leaks.
IMPORTANT
The Clean Air Act of 1990 bans the intentional venting
of (CFC’s and HFC’s) as of July 1, 1992. Approved
methods of recovery, recycling or reclaiming must be
followed. Fines and/or incarceration my be levied for
noncompliance.
WARNING
Fire, Explosion and Personal Safety
Hazard.
Failure to follow this warning could
result in damage, personal injury or
death.
Never use oxygen to pressurize or
purge refrigeration lines. Oxygen,
when exposed to a spark or open
flame, can cause damage by fire
and / or an explosion, that can re-
sult in personal injury or death.
WARNING
Danger of explosion!
When using a high pressure gas such
as dry nitrogen to pressurize a refriger-
ant or air conditioning system, use a
regulator that can control the pressure
down to 1 or 2 psig (6.9 to 13.8 kPa).
Using an Electronic Leak Detector
1 − Connect a cylinder of R−410A to the center port of the
manifold gauge set. Connect manifold gauge to service
valve port.
2 − With both manifold valves closed, open the valve on the
R−410A cylinder.
3 − Open the high pressure side of the manifold to allow the
R−410A into the line set and indoor unit. Weigh in a trace
amount of R−410A.
[A trace amount is a maximum of 2
ounces (57 g) or 3 pounds (31 kPa) pressure.]
Close the
valve on the R−410A cylinder and the valve on the high
pressure side of the manifold gauge set. Disconnect the
R−410A cylinder.
4 − Connect a cylinder of nitrogen with a pressure regulat-
ing valve to the center port of the manifold gauge set.
5 − Connect the manifold gauge set high pressure hose to
the vapor valve service port.
(Normally, the high pres-
sure hose is connected to the liquid line port; however,
connecting it to the vapor port better protects the man-
ifold gauge set from high pressure damage.)
6 − Adjust the nitrogen pressure to 150 psig (1034 kPa).
Open the valve on the high side of the manifold gauge
set which will pressurize line set and indoor unit.
7 − After a few minutes, open a refrigerant port to ensure
the refrigerant you added is adequate to be detected.
(Amounts of refrigerant will vary with line lengths.)
Check all joints for leaks. Purge nitrogen and R−410A
mixture. Correct any leaks and recheck.
B − Evacuating
Evacuating the system of noncondensables is critical for
proper operation of the unit. Noncondensables are defined
as any gas that will not condense under temperatures and
pressures present during operation of an air conditioning
system. Noncondensables and water vapor combine with
refrigerant to produce substances that corrode copper pip-
ing and compressor parts.
NOTE − This evacuation process is adequate for a new
installation with clean and dry lines. If excessive mois-
ture is present, the evacuation process may be required
more than once.
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 20,000 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.