Purging the system
20
Purging the system with a vacuum pump
1. Check that each tube (both liquid and gas side tubes) between the indoor and
outdoor units have been properly connected and all wiring for the test run
has been completed. Remove the service valve caps from both the gas and
the liquid side on the outdoor unit. Note that both the liquid and the gas side
service valves on the outdoor unit are kept closed at this stage.
2. When relocating the unit to another place, perform evacuation using vacuum
pump.
3. Oil trap should be installed every 16'-25' (no oil trap needed when outdoor
unit installed at a lower place than indoor unit).
4. Pipe length and refrigerant amount for single split type air conditioner.
(see tabel 2.2)
Air purging
Max height
difference (B)
(BTU/h)
Cooling capacity
System
Additional amount of
refrigerant to be charged
Connective pipe
length (A)
Use vacuum pump.
Use vacuum pump.
Use vacuum pump.
Use vacuum pump.
Use vacuum pump.
Use vacuum pump.
25'~49'
16'
33'
33'
33'
33'
33'
66'
25'~66'
25'~82'
R410a: 0.22ozs/ft (Pipe length-25')
R410a: 0.22ozs/ft (Pipe length-25')
R410a: 0.16ozs/ft (Pipe length-25')
R410a: 0.22ozs/ft (Pipe length-25')
R410a: 0.16ozs/ft (Pipe length-25')
R410a: 0.54ozs/ft (Pipe length-25')
9000
Heat Pump
Heat Pump
Cooling Only
Cooling Only
Heat Pump
Heat Pump
Heat Pump
12000
21400
21400
25'~82'
25'~82'
25'~82'
18000
18000
Use vacuum pump.
25'~98'
R410a: 0.54ozs/ft (Pipe length-25')
66'
Heat Pump
Use vacuum pump.
25'~98'
R410a: 0.54ozs/ft (Pipe length-25')
28000
33600
Table 2.2
Outdoor unit
Piping length under 16'
Piping length 16' or more
Outdoor unit
Oil trap
Indoor unit
Indoor unit
(A)
(A)
(B)
(B)
