Page 19
Ball Valve (Valve Open)
Schrader valve
service port
service port
cap
stem cap
stem
Use Adjustable Wrench
To open: rotate Stem Clockwise 90°.
To close: rotate Stem Counter-clockwise 90°.
ball
(shown open)
to outdoor coil
to indoor coil
FIGURE 21
IV − CHARGING
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
Leak detector must be capable of sensing HFC
refrigerant.
WARNING
Refrigerant can be harmful if it is inhaled.
Refrigerant must be used and recovered
responsibly.
Failure to follow this warning may result in personal
injury or death.
WARNING
When using a high pressure gas such
as dry nitrogen to pressurize a
refrigeration or air conditioning
system, use a regulator that can
control the pressure down to 1 or 2
psig (6.9 to 13.8 kPa).
WARNING
Fire, Explosion and Personal Safety
Hazard.
Failure to follow this warning could re-
sult 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 could result in per-
sonal injury or death.
Using an Electronic Leak Detector or Halide
1 − Connect a cylinder of HFC−410A to the center port of
the manifold gauge set.
2 − With both manifold valves closed, open the valve on the
HFC−410A cylinder (vapor only).
3 − Open the high pressure side of the manifold to allow the
HFC−410A into the line set and indoor unit. Weigh in a
trace amount of HFC−410A.
[A trace amount is a maxi-
mum 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 HFC−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
HFC−410A mixture. Correct any leaks and recheck.
B − Evacuating the System
Evacuating the system of non−condensables is critical for
proper operation of the unit. Non−condensables are defined
as any gas that will not condense under temperatures and
pressures present during operation of an air conditioning
system. Non−condensables 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 moisture is
present, the evacuation process may be required more
than once.
