Air Purging - Toshiba RAV-GV1601ATP-E Installation Manual

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.
Low pressure gauge High pressure gauge
Gauge manifold
V V
L H
Charge port
Pressure reducing
Gas leak check
Step 1....Pressurize to 0.5 MPa (5 kg/cm 2 G) for 5 minutes or longer.
Step 2....Pressurize to 1.5 MPa (15 kg/cm G) for 5 minutes or longer.
2
Step 3....Pressurize to 4.15 MPa (42 kg/cm
(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
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.
* 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.)
27-EN
CAUTION
Never use oxygen, flammable gas,
or noxious gas for the airtight test.
valve Nitrogen gas
Major leaks can be discovered.
2 G) for 24 hours. ................ Micro leaks can be discovered.
G) per 1°C, so this should be compensated.)
2
Compound
pressure gauge
Pressure gauge
–101 kPa
(–76 cmHg)
Handle Low
Charge hose
Charge hose
(For R32/R410A)
(For R32/R410A)
Vacuum
pump
Charge port
(Valve core
(Setting pin))
Packed valve at gas side
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 charge
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.
Leave the vacuum pump as it is for 1 or 2 minutes, and
check that the indicator of the compound pressure gauge
Open the valve stem or valve handle fully.
(First, at liquid side, then gas side)
Disconnect the charge hose from the charge port.
Tighten the valve and caps of the charge port securely.
Gauge manifold
valve
*1: Use the vacuum pump, vacuum pump adapter, and gauge
manifold correctly referring to the manuals supplied with each
tool before using them.
Handle High
(Keep fully closed) Check that the vacuum pump oil is filled up to the specified line
of the oil gauge.
*2: When air is not charged, check again whether the connecting
port of the discharge hose, which has a projection to push the
valve core, is firmly connected to the charge port.
Vacuum pump adapter
for counterflow
prevention
(For R32/R410A)
– 14 –
Pump down process
■
1. Turn off the Air Conditioner system.
2. Connect the charge hose from the manifold valve to
the service port of the packed valve at gas side.
3. Turn on the Air Conditioner system in cooling
operation more than 10 minutes.
port of the set.
4. Check the operating pressure of the system should
be normal value.
(Ref. with product specification)
Open Handle Low fully.
5. Release the valve rod cap of both service valves.
6. Use the Hexagon wrench to turning the valve rod of
Liquid side fully close.
(*Make sure no entering air into the system)
7. Continue operate Air Conditioner system until and
the gauge of manifold dropped into the range of
0.5 - 0 kgf/cm
8. Use the Hexagon wrench to turning the valve rod of
Retighten the flare nut.
Gas side fully close.
And turn off the Air Conditioner system immediately
thereafter.
9. Remove the gauge manifold from the service port of
the packed valve.
10. Securely tighten the valve rod cap to the both
service valves.
Turn OFF the vacuum pump.
Should be check the compressor operating condition
while pumping down process. It must not any abnormal
does not return.
sound, more vibration. It is abnormal condition appears
and must turn off the Air Conditioner immediately.
2
CAUTION
EN
ID
ID
28-EN