6
4.4. Refrigerant pipe airtight testing method
(1) Connect the testing tools.
• Make sure the stop valves
A
B
are closed and do not open them.
• Add pressure to the refrigerant lines through the service port
C
of the liquid
stop valve
D
.
(2) Do not add pressure to the specified pressure all at once; add pressure little by little.
1
Pressurize to 0.5 MPa (5 kgf/cm
2
G), wait five minutes, and make sure the
pressure does not decrease.
2
Pressurize to 1.5 MPa (15 kgf/cm
2
G), wait five minutes, and make sure the
pressure does not decrease.
3
Pressurize to 4.15 MPa (41.5 kgf/cm
2
G) and measure the surrounding tem-
perature and refrigerant pressure.
(3) If the specified pressure holds for about one day and does not decrease, the pipes
have passed the test and there are no leaks.
• If the surrounding temperature changes by 1 °C, the pressure will change by
about 0.03 MPa (0.3 kgf/cm
2
G). Make the necessary corrections.
(4) If the pressure decreases in steps (2) or (3), there is a gas leak. Look for the
source of the gas leak.
4.5. Stop valve opening method
(1) Gas side of A24-A42 (Fig. 4-5)
Type A
1
Remove the cap, then turn one-quarter rotation counter-clockwise with a flat-bladed
screwdriver to complete open.
2
Check that the valves are fully open, then return the cap to its original state and
tighten it down.
Type B
1
Remove the cap, pull the handle toward you and rotate 1/4 turn in a counterclock-
wise direction to open.
2
Make sure that the stop valve is open completely, push in the handle and rotate
the cap back to its original position.
(2) Liquid side of A24-A42 and Gas/Liquid side of A12, A18 (Fig. 4-6)
1
Remove the cap and turn the valve rod counterclockwise as far as it will go with
the use of a 4 mm hexagonal wrench. Stop turning when it hits the stopper.
(ø6.35, 1/4 inch: Approximately 4.5 revolutions) (ø9.52, 3/8 inch: Approximately
10 revolutions)
2
Make sure that the stop valve is open completely, push in the handle and rotate
the cap back to its original position.
Refrigerant pipes are protectively wrapped for A24-A42
• The pipes can be protectively wrapped up to a diameter of ø90 mm, 3-35/64 inch
before or after connecting the pipes. Cut out the knockout in the pipe cover follow-
ing the groove and wrap the pipes.
Pipe inlet gap for A24-A42
• Use putty or sealant to seal the pipe inlet around the pipes so that no gaps remain.
(If the gaps are not closed, noise may be emitted or water and dust will enter the
unit and breakdown may result.)
I
Double spanner section
(Do not apply a spanner other than to this sec-
tion. Doing so would cause coolant leaks.)
J
Seal section
(Seal the end of the heat insulation material at
the pipe connection section with whatever seal
material you have on hand so that water does
not infiltrate the heat insulation material.)
K
Handle
A
Valve
B
Unit side
C
Operation section
D
Cap
E
Local pipe side
F
Pipe cover
G
Service port
H
Wrench hole
4. Installing the refrigerant piping
A
Stop valve <Liquid side>
B
Stop valve <Gas side>
C
Service port
D
Open/Close section
Fig. 4-4
A
B
H
I
C
D
E
F
G
D
B
A
C
E
Local pipe
F
Sealed, same way for gas side
G
Pipe cover
H
Do not use a wrench here.
Refrigerant leakage may result.
I
Use two wrenches here.
Model
Max height
difference
Additional refrigerant charging amount (kg/oz)
A12, A18
30 m, 100 ft
30 m, 100 ft
0
0.06 kg
0.11 kg
0.17 kg
–
–
–
–
–
–
–
2 oz
4 oz
6 oz
A24, A30, A36
50 m, 165 ft
30 m, 100 ft
0
0.17 kg
0.34 kg
0.51 kg
0.68 kg
0.85 kg
1.02 kg
1.19 kg
1.36 kg
1.53 kg
1.70 kg
6 oz
12 oz
18 oz
24 oz
30 oz
36 oz
42 oz
48 oz
54 oz
60 oz
A42
50 m, 165 ft
30 m, 100 ft
0
0
0
0
0.17 kg
0.34 kg
0.51 kg
0.68 kg
0.85 kg
1.02 kg
1.19 kg
6 oz
12 oz
18 oz
24 oz
30 oz
36 oz
42 oz
Max pipe
length
20 m
25 m
27 m
30 m
33.5 m
36.6 m
40 m
43 m
45.5 m
48.8 m
50 m
70 ft
80 ft
90 ft
100 ft
110 ft
120 ft
130 ft
140 ft
150 ft
160 ft
165 ft
4.6. Addition of refrigerant
• Additional charging is not necessary if the pipe length does not exceed 20 m, 70 ft
for A12-A36, 30 m 100 ft for A42.
• If the pipe length exceeds the specified length above, charge the unit with addi-
tional R410A refrigerant according to the permitted pipe lengths in the chart below.
* When the unit is stopped, charge the unit with the additional refrigerant through
the liquid stop valve after the pipe extensions and indoor unit have been
vacuumized.
When the unit is operating, add refrigerant to the gas check valve using a
safety charger. Do not add liquid refrigerant directly to the check valve.
* After charging the unit with refrigerant, note the added refrigerant amount on
the service label (attached to the unit).
Refer to the “1.5. Using R410A refrigerant air conditioners” for more informa-
tion.
• Be careful when installing multiple units. Connecting to an incorrect indoor unit can
lead to abnormally high pressure and have a serious effect on operation perform-
ance.
(1)
(2)
Fig. 4-5
A
B
C
D
E
F
I
J
J
A
B
K
D
E
F
I
Type A
Type B
Fig. 4-6
B
G
H
E
D
A
I
J
F
BG79U896H02_en
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