Air Purging - Toshiba RAV-GM2241AT8-E1 Installation Manual

Simultaneous triple
Allowable pipe length (m)
Total length Branch piping
• ℓ1 + ℓ2 • ℓ2
Outdoor unit
• ℓ1 + ℓ3 • ℓ3
• ℓ1 + ℓ4 • ℓ4
Maximum Maximum
GM224 100 20
GM280 100 20
Outdoor unit Main pipe
Gas side Liquid side
GM224 Dia. 28.6 Dia. 12.7
GM280 Dia. 28.6 Dia. 12.7
Indoor Unit
Outdoor Unit
Simultaneous double twin
Allowable pipe length (m)
Branch Branch
Total length
piping piping
•ℓ1 +ℓ2 +ℓ4
Outdoor
•ℓ4 •ℓ4 +ℓ2
•ℓ1 +ℓ2 +ℓ5
unit
•ℓ5 •ℓ5 +ℓ2
•ℓ1 +ℓ3 +ℓ6
•ℓ6 •ℓ6 +ℓ3
•ℓ1 +ℓ3 +ℓ7
•ℓ7 •ℓ7 +ℓ3
Maximum
Maximum Maximum
GM224 100 15
GM280 100 15
Outdoor
Main pipe
unit
Gas side Liquid side
GM224 Dia. 28.6 Dia. 12.7
GM280 Dia. 28.6 Dia. 12.7
Indoor Unit
Outdoor Unit
4
31-EN
Height difference (m)
Branch piping Indoor-outdoor H
• ℓ3 – ℓ2
• ℓ4 – ℓ2
Indoor unit: Outdoor unit:
• ℓ4 – ℓ3
Upper Upper
Maximum
10 30 30
10 30 30
Pipe diameter (mm)
Branch piping
Gas side Liquid side
Dia. 15.9 Dia. 9.5
Dia. 15.9 Dia. 9.5
Figure of Simultaneous triple
Indoor Unit
Indoor Unit
4
2 3
1
Height difference (m)
Branch piping Indoor-outdoor H
• (ℓ4 +ℓ2) – (ℓ5 +ℓ2)
• (ℓ4 +ℓ2) – (ℓ6 +ℓ3)
• (ℓ4 +ℓ2) – (ℓ7 +ℓ3)
Indoor Outdoor
• (ℓ5 +ℓ2) – (ℓ6 +ℓ3)
unit: unit:
• (ℓ5 +ℓ2) – (ℓ7 +ℓ3)
Upper Upper
• (ℓ6 +ℓ3) – (ℓ7 +ℓ3)
Maximum
20 6 30 30
20 6 30 30
Pipe diameter (mm)
Branch piping
Gas side Liquid side
ℓ2, ℓ3: Dia. 15.9 ℓ2, ℓ3: Dia. 9.5
ℓ4, ℓ5, ℓ6, ℓ7: Dia. 12.7 ℓ4, ℓ5, ℓ6, ℓ7: Dia. 6.4
ℓ2 to ℓ7: Dia. 15.9 ℓ2 to ℓ7: Dia. 9.5
Figure of Simultaneous double twin
Indoor Unit
Indoor Unit Indoor Unit
5 6 7
2 3
1
6

Air purging

 Airtight Test
Indoor-indoor
(Δh)
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.
0.5
0.5
Low pressure gauge
Number of bent
portions
10 or less
Charge port
10 or less
Gas leak check
Step 1....Pressurize to 0.5 MPa (5 kg/cm²G) for 5 minutes or longer.
Step 2....Pressurize to 1.5 MPa (15 kg/cm²G) for 5 minutes or longer.
Step 3....Pressurize to 4.15 MPa (42 kg/cm²G) 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/cm²G) 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.
Indoor-
indoor
* After the airtight test is completed, evacuate the nitrogen gas.
(Δh)
 Air purge
0.5
With respect to the preservation of the terrestrial
0.5
environment, adopt "Vacuum pump" to purge air
(Evacuate air in the connecting pipes) when installing
the unit.
Number of bent
portions • Do not discharge the refrigerant gas to the
atmosphere to preserve the terrestrial environment.
• Use a vacuum pump to discharge the air (nitrogen,
10 or less
etc.) that remains in the set. If air remains, the
capacity may decrease.
10 or less
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.)
– 16 –
High pressure gauge
CAUTION
Gauge manifold
V V
L H
Never use oxygen, flammable gas, or noxious gas for
the airtight test.
Pressure reducing
valve
Nitrogen gas
Compound
pressure gauge
–101 kPa
(–76 cmHg)
Handle Low
Charge hose
(For R32 or
R410A only)
Charge port
(Valve core
(Setting pin))
Major leaks can be discovered.
Pressure gauge
Gauge manifold
valve
Handle High
(Keep fully closed)
Charge hose (For R32 or
R410A only)
Vacuum pump
adapter for
backflow
prevention
(For R32 or
R410A only)
Vacuum
pump
Packed valve at gas side
32-EN