14-4.Pump Down - Fujitsu AUU7RLF Design & Technical Manual

14-4. Pump down
WARNING
During the pump down operation, make sure that compressor is off before you remove the refriger-
ant piping. Do not remove the connection pipe while the compressor is in operation with valve
open. This may cause abnormal pressure in the refrigeration cycle that leads to breakage and even
injury.
¢ Pump down operation
When moving or discarding the air conditioner, in order to consider the environment and avoid the
discharge of refrigerant to the atmosphere, pump down according to the following procedure.
1. Connect the pressure gauge to the charging port.
2. Change the DIP switch on the board (SET1-2) to On*1
*Be sure the power supply is disconnected on the breaker is turned off when changing the DIP
switch.
3. To start operation, press the [PUMP DOWN] switch*2 for 3 seconds or press after the power
has been on for 3 min.
During pump down, the LED (POWER/MODE) will flash 3 times consecutively.
NOTE: If the [PUMP DOWN] switch is pressed during compressor operation, the compressor
will stop, and the operation will start after about 3 min.
4. Close the liquid pipe valve.
5. When the value between 7.3 psi and 0 psi (0.05 Mpa to 0 Mpa) is shown, close the gas pipe
valve.
6. Stop pump down by pressing the [PUMP DOWN] switch for 3 seconds.
The LED will light as follows.
14-4. Pump down
SET1
ON
1 2 3 4
*1: DIP switch
(SET1-2)
TEST RUN
*2: Push switch (SW1)
S W 1
PUMP DOWN
POWER ERROR
MONITOR
MODE
A B C
(3-blink)
POWER ERROR
MONITOR
MODE
A B C
(3-blink)
- 235 -
D E F
D E F
14. Check and test