20 - 6
Air Conditioning
- Refrigerant Charging and Discharging
Note:
The procedures for refrigerant charging and
discharging must only be carried out by qualified service
personel who have received specialist training on the air
conditioning system.
!
WARNING
The air conditioning system is a closed loop system and
contains pressurised refrigerant. No part of the system
should be disconnected until the system has been
discharged by a refrigeration engineer or a suitable
trained person. You can be severely frostbitten or injured
by escaping refrigerant.
4-3-4-1/2
Charging
This procedure is industry recommended practice for
refilling air conditioning systems with refrigerant.
Evacuate the system beforehand to 740mm (29 in) of
mercury.
1
Close all valves and connect the manifold as shown.
Connect the blue hose to system low pressure and the
red hose to system high pressure. Connect the yellow
hose to the refrigerant cylinder.
2
Invert single valve cylinder on the scales and zero the
scale reading (see
Notes:
for twin valve cylinders).
3
Slowly open the high pressure valve and allow the
vacuum to draw-in refrigerant to the specified weight
for the system. Refer to
Technical Data
.
4
Close all valves and remove the equipment.
Notes:
Add refrigerant as a LIQUID, not as a gas. Some refrigerant
cylinders have separate valves for gas and liquid. Be sure to
connect to the liquid port when following the above
procedure.
Refrigerant can be used either in gas or liquid form. If
recharging with gas follow the manufacturers instructions
and recharge only via the low pressure port. DO NOT use
liquid refrigerant at the low pressure port.
Add refrigerant until the scales indicate the specified weight
for the system or the weight obtained when the system
refrigerant was previously recovered.
To speed up the process a thermostatically controlled
thermal blanket can be used around the replenishing
cylinder.
Section B
9803/3280
Section B
20 - 6
Issue 1
Service Procedures
Lo
Hi
To system Low
Pressure port.
Valve CLOSED
To system High
Pressure port.
Valve OPEN
A396810
Refrigerant
Cylinder
Thermal Blanket
Scales
