1. Preparation for pump down
Confirm that the power is off,
and then open the service panel.
2. Pump down procedure
(1) Check the 3-way valves (both at the liquid side and gas
side) are opened.
(2) Turn the power on.
POWER
MODE
ERROR
TEST
RUN
PUMP
DOWN
LOW NOISE
PEAK CUT
(L1)
(L2)
(L3)
(L4)
(L5)
(L6)
(L7)
(3) Press [PUMP DOWN] switch for 3 seconds or more after
3 minutes after power on.
ERROR
TEST
RUN
PUMP
DOWN
LOW NOISE
PEAK CUT
POWER
MODE
(L1)
(L2)
(L3)
(L4)
(L5)
(L6)
(L7)
LED display lights on as shown in the above figure, and
the fans and the compressor start operating.
If the [PUMP DOWN] switch 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.
ERROR
TEST
RUN
PUMP
DOWN
LOW NOISE
PEAK CUT
POWER
MODE
(L1)
(L2)
(L3)
(L4)
(L5)
(L6)
(L7)
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.
ERROR
TEST
RUN
PUMP
DOWN
LOW NOISE
PEAK CUT
POWER
MODE
(L1)
(L2)
(L3)
(L4)
(L5)
(L6)
(L7)
If the valve on the gas pipe side is not closed, refrigerant
may flow into the piping after the compressor stops
Step (5)
Closing direction
Step (4)
Hexagon wrench
Liquid pipe
Gas pipe
Closing direction
(6) LED display changes after 1 minute as shown in the
figure below
ERROR
TEST
RUN
PUMP
DOWN
LOW NOISE
PEAK CUT
POWER
MODE
(L1)
(L2)
(L3)
(L4)
(L5)
(L6)
(L7)
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.
ERROR
TEST
RUN
PUMP
DOWN
LOW NOISE
PEAK CUT
POWER
MODE
(L1)
(L2)
(L3)
(L4)
(L5)
(L6)
(L7)
PUMP DOWN is completed.
(Note)
To stop pump down, press the [PUMP DOWN] switch
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.
PUMP DOWN (Refrigerant collecting operation)
OUTDOOR UNIT
Perform the following procedures to collect the
refrigerant when moving the indoor unit or outdoor unit
2012.04.26
20
WARNING
Never touch electrical components such as the terminal
blocks or reactor except the switch on the display board.
It may cause a serious accident such as electric shock.
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 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.)
Operate [PUMP DOWN] switch on the display board in
the manner described below.
LED display part
PUMP DOWN
switch
Service port
Service port cap
Service hose
Reactors
Charging port
Charging port cap
3-way valve
Service hose
Terminal blocks
