52
WARNING
Avoid working near flammable materials. Working near flammable materials may cause
explosion or fire. Refrigerant may generate toxic gas if it comes into contact with an open
flame or heated metal.
4. Checking gas leak
a) Remove the charging hose from the
vacuum pump and connect the hose to the
refrigerant cylinder.
b) Loosen the nut on the gauge manifold side
of the charging hose.
c) Open the valve of refrigerant cylinder and
perform air purging in the charging hose.
Then tighten the nut
d) Open the high pressure valve of the gauge
manifold. Charge the system with refrigerant
until the low pressure gauge indicates 57 psi
(390 kPa). After charging is complete, close
the high pressure valve.
e) Open the valve of refrigerant cylinder and
perform air purging in the charging hose.
Then tighten the nut.
f) Check for gas leaks with a gas leak detector.
g) Repair any leak.
5. Evacuation
(repeat)
a) Close the valve of the refrigerant cylinder,
remove the charging hose and connect
the hose to the vacuum pump. Keep the
high and low pressure valves of the gauge
manifold closed.
b) Follow the procedure “Evacuation” on
page 51. Perform evacuation twice or
more to completely remove air or moisture
in the system before charging refrigerant.
LO
Closed
HI
Open
LO
Closed
HI
Closed
R
e
friger
an
t
C
ylinder R-4
10A
Valve Setting
Gauge Reading
57 psi
(390 kPa)
Open High Pressure
Valve
High Pressure
Side Tube
Low Pressure
Valve (Closed)
Process Tube Fitting
Cylinder
Valve
(Open)
Open Valve
Charging Hose
R
e
friger
an
t
C
ylinder R-4
10A
Red Hose
LO
Closed
HI
Closed
Valve Setting
Air Purging
LO
Closed
HI
Open
LO
Closed
HI
Closed
Valve Setting
30 inHg (100 kPa) or larger
High Pressure Valve
High Pressure Gauge
Gauge
High Pressure
Side Tube
Low Pressure
Valve
Charging the System with R-410A Refrigerant