Daikin LREQ15B7Y1R, Installation Manual

Installation manual

21

20B7Y1R

Air cooled refrigeration condensing unit

4P360438-1B – 2014.01

12. TEST RUN

For test run operators

Do not operate the outdoor unit alone on a trial basis.
In a multi-system, all units work together. It is not possible to operate 
the master or a slave unit seperately.

Test run procedure

Use the following procedure to perform a test run after installation 
work is complete for the entire system:

1.

Fully open the shutoff valves on the gas and liquid sides of both 
master and slave unit.

2.

Set the operation switch of the master unit to ON.
Note: Before turning power on, check that the piping cover and 

control box lid of the outdoor unit are closed.

3.

Check the sealing condition of the outdoor unit through the sight 
glass. Make sure that the amount of refrigerant is sufficient.

4.

Make sure that cold air blows from the indoor unit.
Check that the internal temperature is dropping.
(Check that the temperature will drop and reach the set 
temperature in the internal unit.
Check that the indoor unit (for refrigeration or freezing) goes into 
defrosting operation.

5.

Turn power off with the operation switch of the outdoor unit set to OFF.
(Stopping unit operation by disconnecting the power supply directly 
is dangerous. When the unit is stopped in this manner, its power 
outage compensation function may cause it to resume operation as 
soon as the power supply is reactivated. Additionally, stopping the 
unit in this manner may cause the compressor to fail).

Error diagnosis

• If the system cannot operate normal at the time of test run (i.e., the 

H2P indicator is lit), check with malfunction code on the system 
with the pushbutton switches on the PCB of the outdoor unit, and 
take the following steps.

• Check the LED display of the master unit for both master and slave 

unit errors.

If an error occurs, the LEDs of the master unit display can light up in 
the following ways:

Take action according to the status of LED(H7P):

• If H7P is lit, check the malfunction code on the PCB of the 

master unit.

• If H7P is not lit, check the malfunction code on the PCB of the 

slave unit.

• If H7P is blinking, check the malfunction codes on both the PCB 

of the master unit and that of the slave unit.

• To check the malfunction code on one of the PCB’s, refer to 

"How to check malfunction code" on page 21

.

• If one of the units stops functioning due to a compressor 

malfunction, the non-malfunctioning unit will also stop.

How to check malfunction code

By operating the pushbutton switches on the PCB, malfunction 
code items can be displayed on the condensing unit.
1. Make sure that the LED “H1P” is off.

(If the LED is on, press the MODE button (BS1) once.)

2. Press the MODE button (BS1) once. The LED (H1P) starts 

blinking.

3. Press the RETURN button (BS3) to display the first digit of the 

malfunction code on the LED.

4. Press the SET button (BS2) to display the second digit of the 

malfunction code on the LED.

5. Press the MODE button (BS1) to restore the LED to the original 

state.

*1
Set the operation switch of the master unit to the OFF position to reset 
the power supply and then return the operation switch of the master 
unit to the ON position to restart the unit. If the problem persists, refer 
to the Service Manual.
*2
If a transmission error occurs for 2 continuous minutes, the system will 
stop. The corresponding malfunction code is displayed 10 minutes 
after the onset of the error.

CAUTION

• Do not disconnect the power supply for 1 minute after setting the 

operation switch to ON.
Electric leak detection is performed for several seconds after the 
operation switch is set to ON and each compressor starts 
operating, so disconnecting the power supply during that time will 
result in a false detection.

For dealers

• After the test run is finished, check that the piping cover and front 

panel are mounted.

• At the time of delivery to the customer, use the operation manual 

and fully explain the handling of the equipment.

• For precautions at the time of delivery, refer to the provided 

installation manual for each unit as well.

LED (H2P)
LED (H7P)

LED (H2P): ON
LED (H7P): ON

Master unit malfunction

LED (H2P): ON
LED (H7P): OFF

Slave unit malfunction

LED (H2P): ON
LED (H7P): blinking

Master and slave unit
malfunction

BS1

MODE

BS2

SET

BS3

RETURN

BS4

TEST

BS5

RESET

LED indication

(BS3 switch pressed once) (BS2 switch pressed once)

H1P H2P H3P H4P H5P H6P H7P H1P H2P H3P H4P H5P H6P H7P

Installation failure

Remedy

The shutoff valves 
were left closed.

Refrigerant shortage

Over frost formation.
Miss selection of 
expantion valves.
(wet alarm)

Check the 
indoor unit.

The passage of air 
is blocked.
Reverse-phase wiring 
of power supply

Voltage drop

Fully open the 
shutoff valves.

Execessive 
refrigerant charging

Adjust the amount 
of the refrigerant to 
an appropriate level.

Charge additional 
refrigerant.

The shutoff valves 
were left closed.

Fully open the 
shutoff valves.

Remove obstacles that 
block the passage of air.
Exchange two wires out of 
the three power supply wires.

Make a voltage 
drop check.

See *1 below.

Verify power supply 
wiring connections.

– Check if the master is properly 
   designated. 
– Check the transmission wiring.

Electric leak

Transmission 
setting error (*2)

Open L2 phase

Open L1 phase

Normal monitor (HAP) LED off.

OFF

ON

BLINK