Toshiba RAV-SP1404AT-E1 Service Manual page 85

Refrigerant Pipe Length
Single
Allowable pipe length (m)
Total length L
75
Pipe diameter (mm)
Gas side
Ø15.9
Simultaneous twin
Allowable pipe length (m)
Distributed
Total length
pipes
• 1 + 2
System Model
•
• 1 + 3
•
• 1 + 4
•
Maximum
Maximum
SP110 50
TWIN
SP140 50
System Model Main pipe
Gas side
SP110 Ø15.9
TWIN
SP140 Ø15.9
Figure of Single
Indoor Unit
Outdoor Unit
EN-25
Height difference (Indoor-outdoor H) (m)
Indoor unit: Upper Outdoor unit: Lower
30 30
Number of bent portions
Liquid side
10 or less
Ø9.5
Height difference (m)
Distributed Indoor-outdoor H
pipes
2 • 3 – 2
Indoor unit: Outdoor
3 • 4 – 2
Upper unit: Upper
4 • 4 – 3
Maximum
15 10 30 30
15 10 30 30
Pipe diameter (mm)
Branching pipe
Liquid side Gas side Liquid side
Ø9.5 Ø12.7 Ø6.4
Ø9.5 Ø15.9 Ø9.5
Figure of Simultaneous twin
Indoor Unit
Indoor Unit
Distributor
Outdoor Unit
2 3
1
- 13 -
6
AIR PURGING
Airtight test
Before starting an airtight test, further tighten the spindle
valves on the gas side and liquid side.
Pressurize the pipe with nitrogen gas charged from the
service port to the design pressure (4.15 MPa) to
conduct the airtight test.
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.
Indoor-
• Use a vacuum pump to discharge the air (nitrogen,
indoor (Δh)
etc.) that remains in the set. If air remains, the capacity
may decrease.
For the vacuum pump, be sure to use one with a
0.5
backflow preventer so that the oil in the pump does not
0.5 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 R410A, it may cause trouble with the
Number of
refrigeration cycle.)
bent portions
Compound pressure gauge
10 or less
–101 kPa
(–76 cmHg)
10 or less
Handle Low
Charge hose
(For R410A only)
Charge port
(Valve core
(Setting pin))
Vacuum pump
As shown in the figure, connect the charge hose after
the manifold valve is closed completely.
Attach the connecting port of the charge hose with a
projection to push the valve core (setting pin) to the
Turn ON the vacuum pump. (*1)
Loosen the flare nut of the packed valve (Gas side) a
little to check that the air passes through. (*2)
Execute vacuuming until the compound pressure
gauge indicates –101 kPa (–76 cmHg). (*1)
Close Handle Low completely.
Pressure gauge
Gauge manifold valve
Turn OFF the vacuum pump.
Handle High
(Keep fully closed)
Leave the vacuum pump as it is for 1 or 2 minutes, and
Charge hose check that the indicator of the compound pressure
(For R410A only)
Vacuum pump
adapter for counter-
flow prevention
Open the valve stem or valve handle fully. (First, at
(For R410A only)
Vacuum
pump
Disconnect the charge hose from the charge port.
Packed valve at gas side
Tighten the valve and caps of the charge port securely.
charge port of the set.
Open Handle Low fully.
Retighten the flare nut.
gauge does not return.
liquid side, then gas side)
EN-26