Panasonic U-5MX4XPQ, Installation Manual

U-5~18MX4XPQ
Urban Multi air conditioner
4PW28163-1

Installation manual

22

5

Final adjustment of the amount of refrigerant

■

When the unit displays an out of temperature range, the
automatic charging of refrigerant can not be completed.

■

Out of outdoor temperature range

Complete the charging of refrigerant on another time when
the outdoor temperature is warmer than 0°C DB and colder
than 43°C DB.

■

Out of indoor temperature range

Complete the charging of refrigerant on another time when
the indoor temperature is warmer than 20°C DB and colder
than 32°C DB.

In this case, perform a test operation (as explained in the
chapter "12.4. Test operation" on page 25) and the unit will work
properly. (The malfunction code 

U3

  will be displayed on the

indoor unit.)
However, the refrigerant leak detection function can not be used
before completing the refrigerant charging operation and the
judgement of the initial amount of refrigerant by performing the
test operation again.

■

When the temperature has come in range (outdoor = 0~43°C,
indoor 

= 

20~32°C), perform the overcharging judgement

procedure for completion of the refrigerant charging operation.

Overcharging judgement procedure

1

Close all the front panels except the electric box front panel and
the lid on the side of the electric box.

2

Turn  on the power to the outdoor unit and all the connected
indoor units.

3

Press the 

 button once and set the setting model

H1P = OFF.

4

Press and hold the 

 button down for 5 seconds.

The system will start operating.

5

Close all the front panels.

After operating for 40 

minutes, the operation will stop

automatically.

6

After the system has stopped operating, check the display on
the remote controller.

7

If 

E3

, 

F6

 or 

UF

 is displayed on the remote controller as a result of

the overcharge judging operation, recover 20% of the charged
amount of refrigerant and perform the overcharge judgement
procedure again.

■

When there is no more overcharging of refrigerant detected,
restart the automatic refrigerant charging from Start of
automatic charging refrigerant as explained page 18 again.

11.5. Checks after adding refrigerant

■

Are the stop valves for both liquid and gas open?

■

Is the amount of refrigerant, that has been added, recorded?

12. B

EFORE

OPERATION

12.1.

Service precautions

Pay attention to the fan. It is dangerous to inspect the unit while the
fan is running. Be sure to turn off the main switch and to remove the
fuses from the control circuit located in the outdoor unit.

H1P

H2P

H3P

H4P

H5P

H6P

H7P

w c c c w x

x

H1P

H2P

H3P

H4P

H5P

H6P

H7P

w c c c x w x

Make sure to open the stop valves after charging the
refrigerant.

Operating with the stop valves closed will damage the
compressor.

BS1  MODE

BS4  TEST

WARNING: ELECTRIC SHOCK 

Caution when performing service to inverter
equipment

1

Do not open the electric box cover for 10 minutes after
the power supply is turned off.

2

Measure the voltage between terminals on the
terminal block for power supply with a tester and
confirm that the power supply is shut off.

In addition, measure the points, as shown in the figure
below, with a tester and confirm that the voltage of the
capacitor in the main circuit is less than 50 V DC.

3

To  prevent damaging the PC-board, touch a
noncoated metal part to eliminate static electricity
before pulling out or plugging in connectors.

4

The performing of the service to the inverter
equipment must be started after the junction
connectors X1A, X2A,X3A, X4A (X3A and X4A are for
14~18 unit type only) for the fan motors in the outdoor
unit are been pulled out. Be carefull not to touch the
live parts.

(If a fan rotates due to strong wind, it may store
electricity in the capacitor or in the main circuit and
cause electric shock.)

5

After the service is finished, plug the junction
connecter back in. Otherwise the error code 

E7

 will be

displayed on the remote controller and normal
operation will not be performed.

For details refer to the wiring diagram labeled on the back
of the electric box cover.

NOTE

Play it safe!

For protection of the PCB, touch the switch box casing
by hand in order to eliminate static electricity from your
body before performing service.

A2P

A2P

A1P

A3P

TP1 TP2