15
English
2.
After the vacuum drying is finished, charge the additional refrigerant
in its liquid state through the liquid stop valve service port. Taking
into account following instructions:
•
Check that gas and liquid stop valves are closed.
•
Stop the compressor and charge the specified weight of refriger-
ant.
(If the outside unit is not in operation and the total amount cannot be
charged, follow the Additional refrigerant charge procedure (2)
shown below.)
NOTE
•
Procedures for charging additional refrigerant.
(Refer to figure 24)
1.
Pressure reducing valve
2.
Nitrogen
3.
Refrigerant tank
4.
With a siphon
5.
Measuring instrument
6.
Vacuum pump
7.
Valve A
8.
Valve B
9.
Charge hose
10.
Outside unit
11.
Gas side
12.
Liquid side
13.
Discharge gas side
14.
Suction gas side
15.
Stop valve service port
16.
To indoor unit
17.
To indoor units / BS units
18.
Dotted lines represent onsite piping
Additional refrigerant charge procedure (2)-by Additional refriger-
ant charge operation
To learn the system settings for additional refrigerant charging, refer to
the [Service Precaution] label attached on the back of the electric box lid
in the outside unit.
1.
Fully open all stop valves (valve A and valve B must be left
fully closed).
2.
After ten minutes, fully close liquid line stop valve and then, open
the valve by turning 180°.
Start the additional refrigerant charge operation.
See [Service precautions] Label for detail.
If it is difficult to charge the refrigerant additionally, decrease the
water temperature or warm the refrigerant tank.
(Warm the refrigerant tank with a stupe or a warm hot water of
104 °F or less.)
3.
After the system is charged with a specified amount of refrigerant,
press the RETURN button (BS3) on the PC board (A1P) in the out-
side unit to stop the additional refrigerant charge operation.
4.
Immediately open both liquid-side and gas-side stop valve.
(If do not open the stop valve immediately, liquid seal may cause
the pipe to burst.)
NOTE
•
If the refrigerant cylinder is siphonal, set it upright while charging
additional refrigerant.
9-10 Stop valve operation procedure
CAUTION
Do not open the stop valve until 1-6 of “9-8 Checking of device and
installation conditions” are completed. If the stop valve is left open
without turning on power, it may cause refrigerant to buildup in the
compressor, leading to insulation degradation.
Opening stop valve
1.
Remove the cap and turn the valve counterclockwise with the hexa-
gon wrench.
2.
Turn it until the shaft stops.
Do not apply excessive force to the stop valve. Doing so may break
the valve body, as the valve is not a backseat type. Always use the
special tool.
3.
Make sure to tighten the cap securely.
Closing stop valve
1.
Remove the cap and turn the valve clockwise with the hexagon
wrench.
2.
Securely tighten the valve until the shaft contacts the main body
seal.
3.
Make sure to tighten the cap securely.
∗
For the tightening torque, refer to the table on the below.
Tightening torque
(Refer to figure 25)
1.
Service port
2.
Cap
3.
Hexagon hole
4.
Shaft
5.
The main body seal
〈
Caution
〉
• Do not damage the cap sealing.
• Always use a charge hose for service port connection.
• After tightening the cap, check that no refrigerant leaks are present.
• After working, securely tighten the cover of service port without fail
by specified torque.
• When loosening a flare nut, always use two wrenches in combina-
tion. When connecting the piping, always use a spanner and torque
wrench in combination to tighten the flare nut.
• When connecting a flare nut, coat the flare (inner and outer faces)
with ether oil or ester oil and hand-tighten the nut 3 to 4 turns as the
initial tightening.
• Do not forget to open the stop valve before starting operation.
(Refer to figure 26)
1.
Remove the cap and turn the valve counterclockwise with
the hexagon wrenches until it stops.
2.
Discharge gas side
3.
Liquid side
4.
Suction gas side
5.
Never remove the partition flange for any reason.
6.
Full close on the suction gas side
Stop
valve size
Tightening torque ft.-lbf. (Turn clockwise to close)
Shaft
(valve body)
Cap
(valve lid)
Service port Flare nut
Gas side
accessory
pipe (1)
Liquid
side
3.98-4.87
Hexagonal
wrench 1/8 in.
9.95-12.17
8.48-10.25
24.1-29.4
_
Gas
side
19.91-24.33
Hexagonal
wrench 3/8 in.
26.54-32.44
8.48-10.25
_
16.22-20.65
