Installation manual
9
250B8W1B
Split system air conditioner
4PW25544-1A
8
Calculation coefficients
9
See the examples below for a clear understanding.
Total charging weight of the refrigerant (after a leak,
etc.)
■
The total charging amounts relate to the refrigerant piping length
as in
"Maximum total one way piping length"
paragraph
"7.4. Allowable pipe length and height difference" on
, the factory charging amount is mentioned on the
nameplate label.
For the total charging amount refer to the additional refrigerant
charge sticker mounted on the unit.
Precaution for pumping-down operation
Take the following steps to perform the pumping-down operation.
This is the end of pumping-down operation. After pumping-down
operation, the remote controller can show the following pattern:
-
"
U4
"
-
blank screen
-
indoor fan operates for about 30 seconds
Even when ON button on the remote controller is pressed, it will not
operate. Turn off the main power supply switch and turn it on again in
need of operation.
Be sure to re-open stopvalves before re-starting the unit operation.
Ø
Coefficient
12.7
0.09
9.5
0.05
6.4
0.03
Example 1
L=80 m
Ø12.7
Chargeless length = 30 m
Additional refrigerant charge = (80-30)x0.09 = 50x0.09 = 4.5 kg
Example 2
L2=7 m
100 type
Ø9.5
200 type
L1=35 m
indoor
Ø9.5
L3=5 m
100 type
Ø9.5
Chargeless length = 30 m
Additional refrigerant charge
= ((35+7+5)–30)x0.05 = 17x0.05 = 0.85 kg = 0.9 kg
Example 3
L2=7 m
60 type
Ø6.4
200 type
L1=5 m
L3=17 m
60 type
Ø9.5
Ø6.4
L4=10
m
60 type
Ø6.4
Chargeless length = 30 m
Ø9.5
(30-5) = 25 m
Ø6.4
25–(7+17+10) = –9 m
Additional refrigerant charge = 9x0.03 = 0.27 kg = 0.3 kg
Example 4
L4=10 m
60 type
Ø6.4
L2=5 m
Ø9.5
L5=7 m
60 type
Ø6.4
250 type
L1=25 m
Ø12.7
L6=7 m
60 type
Ø6.4
L3=5 m
Ø9.5
L7=5 m
60 type
Ø6.4
Chargeless length = 30 m
Ø12.7 (30-25) = 5 m
Ø9.5
5–(5+5) = –5 m
Ø6.4
10+7+7+5 = 29 m
Additional refrigerant charge = (5x0.05)+(29x0.03) = 1.12 kg = 1.1 kg
In case of complete recharge of the refrigerant, please first
execute vacuuming. Vacuuming must be executed using
the both 2 service ports situated on the piping inside the
airconditioning outdoor unit simultaneously.
Make sure that both stop valves are open for vacuuming.
Vacuuming can not be executed completely using the ports
on the stop valves.
Procedure
Precaution
1
Stop the unit from operating.
Use the remote controller.
2
Put a pressure gauge at the
service port of the gas stop
valve.
Use a pressure gauge
reserved for R410A
exclusively.
3
Close the stop valve on the
liquid side securely and open
the the gas side completely.
Insecure closing of the valve
may result in burning of the
compressor.
4
Start the fan operation with the
remote controller.
Confirm that the stop valve:
• on the liquid is closed
• on the gas side is open.
5
Push the pumping-down
button (BS5) on the PC board
of the outdoor unit for more
than 5 seconds.
The H2P led will flash.
Compressor and outdoor fan
will start operation
automatically.
If step 5 is performed before
step 4, then the indoor fan
may automatically start
running. Please pay attention
to this.
6
Continue operation (automatic
operation) for a maximum of
20 minutes.
—
7
The unit stops working. At this
time, close the stop valve on
the gas side.
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