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8.
INSPECTION AND PIPE INSULATION
To Piping and Electric Wiring Contractors
• Be sure to use nitrogen gas for airtight tests.
• Do not open a shutoff valve until the insulation of the main power
supply circuit is measured. Insulation degradation may result if
the insulation is measured with the shutoff valve opened.
8-1 Testing Instruments
Compatibility with conventional tool
Name
(for other types of refrigerant)
• Use a pressure-resistant product withstand-
ing a minimum pressure of 12.3 MPa.
• Use an end connector suited to the shape
Charge
of the service ports of the outdoor unit.
hose
Shape of service ports of outdoor unit
(on liquid and gas sides): 1/4Swagelok
• Use a pressure-resistant pressure gauge
and valve withstanding a minimum pressure
of 12.3 MPa.
Gauge
• At the time of vacuum drying, connect a
manifold
negative pressure gauge to the outlet of the
vacuum pump and check the degree of vac-
uum.
Reguretar
• Use a pressure-resistant product withstand-
(Pressure
ing a minimum pressure of 12.3 MPa.
regulator)
• Pay the utmost attention that pump oil will
not flow back to the system while the pump
Vacuum
is not in operation.
pump
• Use a product that makes evacuation possi-
ble down to –100.7 kPa (5 Torr, –755 mmHg).
8-2 Operation method of shutoff valve
Take the following procedure to operate the shutoff valve.
CAUTION
• Do not open the shutoff valve until all the items specified in
"8-6 Checking of device and installation conditions" in the
installation manual are completed.
• The shutoff valve is of back seat type. Be sure to turn and loosen
the packing bush 1/4 rotation when opening or closing the valve.
Be sure to tighten the packing bush securely after the valve is
opened or closed.
• After the operation of the valve is completed, be sure to mount the
valve cover packing provided to the valve and tighten the cap.
• After tightening the packing bush and cap, be sure to check that
there is no refrigerant gas leakage.
• Be sure to use a dedicated tool at the time of handling the shutoff
valve. The valve may be damaged if excessive force is imposed.
• If the shutoff valve is left opened without power supplied, refriger-
ant will be condensed in the compressor and the insulation of the
main power circuit will be degraded.
Tightening torque
Check the sizes of shutoff valves mounted to each model and the
tightening torque of each valve from the following table.
Tightening torque N·m
(Turn clockwise to close)
Shutoff valve
Shaft (valve body)
position
Shutoff
valve open
valve closes
Liquid side
8.8 - 10.8
13.5 - 16.5
shutoff valve
Gas side
8.8 - 10.8
15.5 - 18.9
shutoff valve
English
Cap
Service
Shutoff
(valve lid)
port
34 - 38
3.0 - 5.0
<State before shipping>
Inside equipment
Shaft
Front seat
Back seat
Outside equipment
(onsite piping side)
Method of opening
(1) Remove the cap and turn the packing bush counterclockwise
1/4 rotation.
(2) Tighten the shaft until the shaft comes in contact with the front seat.
(3) Turn and loosen the packing bush clockwise 1/4 rotation.
(4) Check that there is no refrigerant gas leakage from the valve
packing or shaft. (If there is leakage, further tighten the shaft.)
(5) Insert the valve cover packing into the cap, and tighten the cap
securely.
Method of closing
(1) Remove the cap and turn the packing bush counterclockwise
1/4 rotation.
(2) Tighten the shaft until the shaft comes in contact with the back seat.
(3) Turn and loosen the packing bush clockwise 1/4 rotation.
(4) Check that there is no refrigerant gas leakage from the valve
packing or shaft. (If there is leakage, further tighten the shaft.)
(5) Insert the valve cover packing into the cap, and tighten the cap
securely.
8-3 Operation method of service port
Note
• Conduct an airtight test and vacuum dry-
ing infallibly through the service port for
both liquid and gas shutoff valves.
• Refer to the integrated label on the front
panel of the outdoor unit for the position of
the service port.
Connecting charge hose
(1) Remove the nut of the service port after loosening the nut a little
with a spanner and checking that no gas is coming out.
(2) Apply PAG oil to the seal, and hold and screw in the nut of the
charge hose by hand.
(3) Further tighten the nut with a spanner by 30° to 45°.
(4) Check that there is no refrigerant gas leakage from the nut and
plug. If there is any refrigerant gas leakage, further tighten them.
<Opening or closing state before shipping>
Inside equipment
Outside equipment
(onsite piping side)
Service port
(1/4Swagelok)
Packing bush
Valve cover packing
Cap
Label
Charge hose
Nut of service port
Seal
11
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