RAC Split Units

Document Sample
RAC Split Units Powered By Docstoc
					                    LG Air conditioning RAC unit Fault code sheet



                               RAC Split Units
If there is fault on any LG RAC unit a two digit number will appear on the units led
display. If the system has no led display the fault indication will be shown on the fan
coil using 2 LEDs on the indoor unit display panel


The codes are explained in detail below.




                       Hendra June 2006 RAC Fault Codes
                                                                                  1
                                    LG Air conditioning RAC unit Fault code sheet


Fault code 01

Is a fault with the Indoor unit return air Thermistor

Unplug the Thermistor from the PCB and Check its resistance check against this
graph:


                                             resistance of Air thermistor

                        120
    Resistance k Ohms




                        100
                        80
                        60
                        40
                        20
                         0
                              -20   -10        0       10        20        30        40    50   60
                                                            Temperature



Alternatively the sensor can be tested while still connected to the PCB measure the
DC voltage across the resistor and check it against the graph below.


                                            Voltage across Air thermistor

                        5.0
                        4.5
                        4.0
    Volts DC




                        3.5
                        3.0
                        2.5
                        2.0
                        1.5
                        1.0
                              -20    -10           0        10        20        30        40    50
                                                            Temperature




                                          Hendra June 2006 RAC Fault Codes
                                                                                                2
                                       LG Air conditioning RAC unit Fault code sheet


Fault code 02

Is a problem with the Indoor unit coil Thermistor

Unplug the Thermistor from the indoor PCB and Check its resistance against this
graph:


                                             Coil thermistor resistance k Ohms

                           50
       Resistance k Ohms




                           40

                           30

                           20

                           10

                           0
                                -20    -10       0    10    20    30     40     50     60   70
                                                           Temperature



Alternatively the sensor can be tested while still connected to the PCB measure the
DC voltage across the resistor and check it against the graph below.


                                              Voltage across coil thermistor
                           5.0

                           4.0
       Volts DC




                           3.0

                           2.0

                           1.0

                           0.0
                                 -20    -10      0    10    20     30    40     50     60   70
                                                              Temp




                                         Hendra June 2006 RAC Fault Codes
                                                                                                 3
                   LG Air conditioning RAC unit Fault code sheet


Fault Code 03

The 03 fault code indicates a communication error between the remote controller and
the indoor unit PCB. As RAC product cannot have a wired remote controller this fault
is either within the indoor unit pcb or the infra red receiver pcb. Check the two PCBs
are correctly connected together and if so you will need to replace both to solve the
problem.




                      Hendra June 2006 RAC Fault Codes
                                                                                4
                                    LG Air conditioning RAC unit Fault code sheet


Fault Code 04

Is a fault with the Outdoor unit inverter Heat sink Thermistor, the fault will occur if the
sensor is faulty or the heat sink temperature exceeds 85ºC.

Unplug the Thermistor from the PCB and Check its resistance check against this
graph:


                                             resistance of Air thermistor

                        120
    Resistance k Ohms




                        100
                        80
                        60
                        40
                        20
                         0
                              -20   -10        0       10        20        30        40    50   60
                                                            Temperature



Alternatively the sensor can be tested while still connected to the PCB measure the
DC voltage across the resistor and check it against the graph below.


                                            Voltage across Air thermistor

                        5.0
                        4.5
                        4.0
    Volts DC




                        3.5
                        3.0
                        2.5
                        2.0
                        1.5
                        1.0
                              -20    -10           0        10        20        30        40    50
                                                            Temperature




                                          Hendra June 2006 RAC Fault Codes
                                                                                                5
                     LG Air conditioning RAC unit Fault code sheet


Fault code 05

This fault code indicates a communication error between the indoor and outdoor
units; this is usually caused by wiring errors or condensate pumps connected to the
inter-connecting cable.

The communication between the units is a fluctuating DC voltage which can be easily
lost if the wiring is not done correctly. If there is a communication error fault CH05 will
appear within 5 mins of powering up the system.

Testing
Turn on the power and start the indoor unit in cooling, set the temperature to 18ºC,
the serial communication signal will only be present for the first 3 mins of operation.

Set your meter to DC Volts, Test between terminals 2 and 3, of the outdoor unit and
wiring terminals you should see 0-65 V dc, it will be fluctuating.

If the Voltage is not present disconnect the inter unit wiring, test the Voltage on the
wiring terminals again, If No Voltage is present the outdoor PCB must be faulty.

Once the signal has been detected leaving the outdoor unit check what is being
received by the indoor unit, measure DC Voltage across the wiring terminal 2 and 3,
it should be identical to what you saw at the outdoor unit, if not your wiring is at fault.



Fault code 06

This fault is caused by an over current in the inverters DC power circuit. This is
caused by either the inverter PCB or compressor being short circuit or down to earth.

Check the resistance of the compressor windings with the electrical connections
disconnected, typically they should be between 1 and 5 Ohms each.

If the compressor is OK check the inverter output voltages are all equal.



Fault Code 07

This fault is caused by a Compressor over-current see code 06




                        Hendra June 2006 RAC Fault Codes
                                                                                     6
                    LG Air conditioning RAC unit Fault code sheet


Fault Code 08

This fault is caused by the Indoor fan being locked;

Check the fan motor is plugged into the indoor PCB correctly; check the fan motor is
turning, if not check the AC Voltage supplied to the fan motor, this will vary from 120
V ac at low speed to 170V AC at high speed.
If no Voltage is present the PCB is faulty, if the Voltage is present the fan motor will
be Faulty.




Fault Code 09

This is an Outdoor unit fan motor fault

Check the fan motor is plugged into PCB correctly; Start the unit up the fan motor
should turn when the compressor is running.

Check the fan motor is turning, if not check the Voltages supplied to the fan motor,
there will be a connector on the pcb with five wires, measure
from red to Black it should be 300 - 320V DC,
From white to Black it should be 10-15V DC,
If no Voltage is present the PCB is faulty, if the Voltage is present the fan motor will
be Faulty.




                       Hendra June 2006 RAC Fault Codes
                                                                                    7
                                     LG Air conditioning RAC unit Fault code sheet


Fault Code 10

This fault is caused by the compressor discharge sensor reading over 130ºC or the
discharge Thermistor being faulty.

Reset the power, if the fault goes away and the compressor starts check the
discharge temperature, if it is very hot check the refrigerant charge. High discharge
temperatures are usually caused by shortage of refrigerant.

If the unit wont restart after resetting the power check the Thermistor, Unplug the
Thermistor from the PCB and Check its resistance check against this graph:


                                         Resistance of discharge pipe thermistor

                         800
                         700
      resistance kOhms




                         600
                         500
                         400
                         300
                         200
                         100
                           0
                               -20 -10     0    10    20    30        40        50    60    70    80   90 100 110
                                                                       temp


Alternatively the sensor can be tested while still connected to the PCB measure the
DC voltage across the resistor and check it against the graph below.


                                           Voltage across discharge thermistor

                         5.0
                         4.5
                         4.0
        Voltage DC




                         3.5
                         3.0
                         2.5
                         2.0
                         1.5
                         1.0
                               -20 -10    0    10    20    30    40        50    60    70    80   90 100 110 120
                                                                      Temp




                                          Hendra June 2006 RAC Fault Codes
                                                                                                                8

				
DOCUMENT INFO