11
8.3. Refrigerant collecting (pump down)
Perform the following procedures to collect the refrigerant when moving the indoor
unit or the outdoor unit.
1
Supply power (circuit breaker).
* When power is supplied, make sure that “CENTRALLY CONTROLLED” is not
displayed on the remote controller. If “CENTRALLY CONTROLLED” is dis-
played, the refrigerant collecting (pump down) cannot be completed normally.
* Start-up of the indoor-outdoor communication takes about 3 minutes after the
power (circuit breaker) is turned on. Start the pump-down operation 3 to 4
minutes after the power (circuit breaker) is turned ON.
2
After the liquid stop valve is closed, set the SWP switch on the control board of
the outdoor unit to ON. The compressor (outdoor unit) and ventilators (indoor and
outdoor units) start operating and refrigerant collecting operation begins. LED1
and LED2 on the control board of the outdoor unit are lit.
* Only set the SWP switch (push-button type) to ON if the unit is stopped. How-
ever, even if the unit is stopped and the SWP switch is set to ON less than 3
minutes after the compressor stops, the refrigerant collecting operation cannot
be performed. Wait until compressor has been stopped for 3 minutes and then
set the SWP switch to ON again.
3
Because the unit automatically stops in about 2 to 3 minutes when the refrigerant
collecting operation is completed (LED1 off, LED2 lit), be sure to quickly close the
gas stop valve. If LED1 is lit and LED2 is off and the outdoor unit is stopped, refrig-
erant collection is not properly performed. Open the liquid stop valve completely,
and then repeat step
2
after 3 minutes have passed.
* If the refrigerant collecting operation has been completed normally (LED1 off,
LED2 lit), the unit will remain stopped until the power supply is turned off.
4
Turn off the power supply (circuit breaker).
* Note that when the extension piping is very long with large refrigerant amount,
it may not be possible to perform a pump-down operation. When performing
the pump-down operation, make sure that the low pressure is lowered to near
0 MPa (gauge).
Warning:
When pumping down the refrigerant, stop the compressor before disconnect
-
ing the refrigerant pipes. The compressor may burst if air etc. get into it.
8. Special Functions
1 2 3 4 5 6
* Set the refrigerant address using the DIP switch of the outdoor unit.
1
Wiring from the Remote Control
This wire is connected to TB5 (terminal board for remote controller) of the indoor
unit (non-polar).
2
When a Different Refrigerant System Grouping is Used.
Up to 16 refrigerant systems can be controlled as one group using the slim MA
remote controller.
Note:
In single refrigerant system (twin/triple), there is no need of wiring
2
.
A
Outdoor unit
B
Indoor unit
C
Master remote controller
D
Subordinate remote controller
E
Standard 1:1 (Refrigerant address = 00)
F
Simultaneous twin (Refrigerant address = 01)
G
Simultaneous triple (Refrigerant address = 02)
E
SW 1 - 3 ~ 6
F
SW 1 - 3 ~ 6
G
SW 1 - 3 ~ 6
9. System control (Fig. 9-1)
Fig. 9-1
SW1
Function table
<SW1>
Function
Operation according to switch setting
ON
OFF
SW1
function
settings
1
Compulsory
defrosting
Start
Normal
2
Error history
clear
Clear
Normal
3
4
5
6
Refrigerant
system ad-
dress setting
Settings for outdoor unit addresses
0 to 15
TB1
A
G
F
A
A
E
B
B
B
B
B
B
D
C
TB1
TB1
TB4
TB5
TB4
TB5
TB4
TB4
TB5
TB4
TB4
1
1
2
ON
OFF
ON
OFF
ON
OFF
3 4 5 6
3 4 5 6
3 4 5 6
ON
OFF
2
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