Pump Down - Fujitsu ARYG72LHTA Service Instruction

1-14. 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 remove the refrigerant piping.
Do not remove the connection pipe while the compressor is in operation with 2-way
or 3-way valve open. This may cause abnormal pressure in the refrigeration cycle
that leads to breakage and even injury.
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 pump down is
completed in all outdoor units.
(Group control system installation described in "SPECIAL INSTALLATION
METHODS" in the installation manual of the indoor unit.)
Please check the refrigerant circuit for any leaks before starting the pump down
operation.
Do not proceed with the pump down operation if there is no refrigerant left in the
circuit due to bent or broken piping.
• Operate "PUMP DOWN" button on the display board in the manner described
below.
14.1. Preparation for pump down
• Confirm that the power is off, and then open the service panel.
CAUTION
14.2. Pump down procedure
(1) Check the 3-way valves (both the liquid side and gas side) are opened.
(2) Turn the power on.
PUMP
POWER/
DOWN
ERROR
MODE
(L1)
● ○ ○
○ ●
Sign " ": Lights off, " ": Lights on
(3) Press "PUMP DOWN" button for 3 seconds or more after 3 minutes after power on.
PUMP
POWER/
DOWN
ERROR
MODE
(L1)
● ○ ●
○ ●
Sign " ": Lights off, " ": Lights on
LED display lights on as shown in the above figure, and the fans and the
compressor start operating.
• If the "PUMP DOWN" button is pressed while the compressor is operating, the
compressor will stop, then start again in about 3 minutes.
(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.
PUMP
POWER/
DOWN
ERROR
MODE
(L1)
● ○ ●
○ ●
Sign " ": Lights off, " ": Lights on
• If the valve on the liquid pipe side is not closed, the pump down cannot be
performed.
(5) When LED display changes as shown in the below figure, close the 3-way valve on
the gas pipe side tightly.
PUMP
POWER/
DOWN
ERROR
MODE
(L1)
● ○ ●
○ ●
Sign " ": Lights off, " ": Lights on
• If the valve on the gas pipe side is not closed, refrigerant may flow into the piping
after the compressor stops.
Step (4)
Closing direction
Hexagon wrench
Liquid pipe
(6) LED display changes after 1 minute as shown in the figure below.
PUMP
POWER/
DOWN
ERROR
MODE
(L1)
● ○ ●
○ ●
Sign " ": Lights off, " ": Lights on
Fans and compressor stop automatically.
• If the pump down is successfully completed (the above LED display is shown), the
outdoor unit remains stopped until the power is turned off.
(7) Turn the power off.
PUMP
POWER/
DOWN
ERROR
MODE
(L1)
○ ○ ○
○
Sign " ": Lights off
PUMP DOWN is completed.
(Note)
• To stop pump down, press the "PUMP DOWN" button again.
• To start the pump down again after the compressor is automatically stopped due to an
error, turn the power off and open the 3-way valves. Wait 3 minutes, turn the power on
and start the pump down again.
• When starting the operation after completion of the pump down, turn the power off,
and then open the 3-way valves. Wait 3 minutes, turn the power on and perform a test
run in the "COOL" operation mode.
• If an error occurs, recover the refrigerant from service port.
01-13
LOW PEAK
NOISE CUT
(L2) (L3) (L4) (L5) (L6)
○ ○ ○ ○
LOW PEAK
NOISE CUT
(L2) (L3) (L4) (L5) (L6)
○ ○ ● ●
LOW PEAK
NOISE CUT
(L2) (L3) (L4) (L5) (L6)
○ ○ ○ ●
LOW PEAK
NOISE CUT
(L2) (L3) (L4) (L5) (L6)
○ ○ ○ ○
Step (5)
Closing direction
Gas pipe
LOW PEAK
NOISE CUT
(L2) (L3) (L4) (L5) (L6)
○ ○ ○ ○
LOW PEAK
NOISE CUT
(L2) (L3) (L4) (L5) (L6)
○ ○ ○ ○
○
●
●
●
○
○