Air Purging - Toshiba RAV-SP404AT-E Installation Manual

Super Digital Inverter
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. Perform gas leak checks using a leak tester for
the HFC refrigerant.
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 R410A, it may cause trouble with the refrigeration
cycle.)
Compound pressure gauge
–101 kPa
(–76 cmHg)
Handle Low
Charge hose
(For R410A only)
Charge port
(Valve core (Setting pin))
EN
Pressure gauge
Gauge manifold valve
Handle High
(Keep fully closed)
Charge hose
(For R410A only)
Vacuum pump adapter for
counter-flow prevention
(For R410A only)
Vacuum
pump
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.
Turn OFF the vacuum pump.
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
Disconnect the charge hose from the charge port.
Tighten the valve and caps of the charge port securely.
*1
Use the vacuum pump, vacuum pump adapter, and gauge
manifold correctly referring to the manuals supplied with each
tool before using them.
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.
15
port of the set.
Open Handle Low fully.
Retighten the flare nut.
does not return.
side, then gas side)