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Simultaneous twin
Outdoor unit
Allowable pipe length (m)
Height difference (m)
Total length
•
1
+
2
•
1
+
3
Maximum
Branch piping
•
2
•
3
Maximum
Branch piping
•
3
–
2
Maximum
Indoor-outdoor H
Indoor-indoor
(
Δ
h)
Indoor unit:
Upper
Outdoor unit:
Upper
GP80, 110
50
15
10
30
30
0.5
GP140
50
15
10
30
30
0.5
Outdoor unit
Pipe diameter (mm)
Number of bent
portions
Main pipe
Branch piping
Gas side
Liquid side
Gas side
Liquid side
GP80, 110
15.9
9.5
12.7
6.4
10 or less
GP140
15.9
9.5
15.9
9.5
10 or less
2
3
H
1
Figure of simultaneous twin
Indoor unit
Outdoor unit
Indoor unit
6
AIR PURGING
Airtight Test
After completing the refrigerant piping work, perform an airtight test. Connect a nitrogen gas cylinder and pressurize
the pipes with nitrogen gas as follows to conduct the airtight test.
Gas leak check
* After the airtight test is completed, evacuate the nitrogen gas.
Air Purge
With respect to the preservation of the terrestrial
environment, adopt “Vacuum pump” to purge air
(Evacuate air in the connecting pipes) when installing the
unit.
• Do not discharge the refrigerant gas to the
atmosphere to preserve the terrestrial environment.
• Use a vacuum pump to discharge the air (nitrogen,
etc.) that remains in the set. If air remains, the capacity
may decrease.
For the vacuum pump, be sure to use one with a
backflow preventer so that the oil in the pump does not
backflow into the pipe of the air conditioner when the
pump stops.
(If oil in the vacuum pump is put in an air conditioner
including R32, it may cause trouble with the refrigeration
cycle.)
Step 1....Pressurize to
0.5 MPa
(5 kg/cm
2
G) for 5 minutes or longer.
Major leaks can be discovered.
Step 2....Pressurize to
1.5 MPa
(15 kg/cm
2
G) for 5 minutes or longer.
Step 3....Pressurize to
4.15 MPa
(42 kg/cm
2
G) for 24 hours. ................ Micro leaks can be discovered.
(However, note that when the ambient temperature differs during pressurization and after 24 hours, the pressure will
change by approximately 0.01 MPa (0.1 kg/cm
2
G) per 1°C, so this should be compensated.)
If the pressure drops in steps 1 through 3, check the connections for leakage.
Check for leaks with foaming liquid, etc., take steps to fix the leaks such as brazing the pipes again and tightening
the flare nuts, and then perform the airtight test again.
V
L
V
H
Charge port
Low pressure gauge
High pressure gauge
Gauge manifold
Pressure reducing
valve
Nitrogen gas
CAUTION
Never use oxygen, flammable gas,
or noxious gas for the airtight test.
Pressure gauge
Gauge manifold valve
Handle High
(Keep fully closed)
Compound pressure gauge
Charge hose
(For R32 or R410A
only)
Vacuum
pump adapter
for backflow
prevention
(For R32 or
R410A only)
–101 kPa
(–76 cmHg)
Handle Low
Charge hose
(For R32 or R410A
only)
Charge port
(Valve core
(Setting pin))
Packed valve at gas side
Vacuum
pump
EN-161
EN-162
Summary of Contents for RAV-GP1101AT-E
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