Pump Down - Fujitsu AUXG18KVLA Design & Technical Manual

9-3. Pump down

WARNING
• Never touch electrical components such as the terminal blocks except the button on the display
board. It may cause a serious accident such as electric shock.
• During the pump-down operation, make sure that the compressor is turned off before you re-
move the refrigerant piping.
Do not remove the connection pipe while the compressor is in operation with 2-way or g. 3-way
valve open. This may cause abnormal pressure in the refrigeration cycle that leads to breakage
and even injury.
CAUTION
• Perform the pump down operation before disconnecting any refrigerant pipe or electric cable.
• Collect refrigerant from the service port or the 3-way valve if pump down cannot be performed.
• In case of a group control system installation, do not turn the power off until pump down is com-
pleted in all outdoor units.
(Group control system installation described in "SPECIAL INSTALLATION METHODS" in the in-
stallation manual of the indoor unit.)
¢ Pump down procedure
Confirm that the power is off, and then open the service panel.
Symbols in the following table indicate LED status.
"○": Lights off, "●": Lights on
1. Check the 3-way valves (both the liquid side and gas side) are opened.
2. Turn the power on.
3. Press [PUMP DOWN] button for 3 seconds or more after 3 minutes after power on.
LED display lights on as shown in the above figure, and the fans and the compressor start op-
erating.
NOTE: If the [PUMP DOWN] button is pressed during compressor operation, the compres-
sor will stop, and the operation will start after about 3 min.
4. LED display will change as shown below about 3 minutes after the compressor starts. Fully
close the 3-way valve on the liquid pipe side at this stage.
NOTE: If the valve on the liquid pipe side is not closed, the pump down cannot be per-
formed.
9-3. Pump down
PUMP
POWER
ERROR
DOWN
MODE (L1)
● ○ ○
PUMP
POWER
ERROR
DOWN
MODE (L1)
● ○ ●
PUMP
POWER
ERROR
DOWN
MODE (L1)
● ○ ●
- 196 -
LOW PEAK
NOISE CUT
(L2) (L3) (L4) (L5)
○ ○ ○ ○
LOW PEAK
NOISE CUT
(L2) (L3) (L4) (L5)
○ ○ ● ●
LOW PEAK
NOISE CUT
(L2) (L3) (L4) (L5)
○ ○ ○ ●
(L6)
○
(L6)
●
(L6)
●
9. Check and test