Mitsubishi mr slim troubleshooting

Central controller: 6600

Description : Duplicate address, Lossnay units attached with the same address.

Cause : Units attached with the same address

Check procedure : Change the address and reset the unit’s power

Central controller: 6602

Description: Hardware error of transmission processor. It is also termed as Lossnay board fault.

Cause:

1. The waveform is transformed on transmission wiring.
2. Lossnay board fault

Check procedure: You have to simply check the comms wiring.

Central controller: 6603

Description: The transmission line is busy when Mr. Slim is connected to the M-net transmission line.

Cause: Its cause is no data could be transmitted for 8 minutes.

Check procedure: Check A-MNetconnections(TB7)

Central controller: 6606

Description: This error indicates the communication error with a communication processor.

Cause: The main cause is that the Lossnay address is not transmitted.

Check procedure: Check M.Net voltage

Central controller: 6607

Description: This error indicates:

• Communication error
• Range of transmission wiring exceeded
• Faulty A-MNet converter

Cause:

1. Range of transmission wiring exceeded
2. Faulty A-MNet converter

Check procedure Check the M-Net wiring. Check your M-Net voltage. Replace the M-Net converter.

Central controller: 6608

Description: It indicates M-Net no response or you can say communication error.

Cause:

1. Range of the transmission wiring exceeded
2. Faulty A-MNet converter
3. The incorrect wire is used for the M-Net connection.

Check procedure: Check your M-Net wiring and the cable type used should be 2-core screened CY cable, 1.5mm

Central controller: 6844

Description: This error is caused when more than 1 unit is connected in a group resulting in miswiring or communication error.

Cause:

1. Miswiring
2. Loose interconnecting cables
3. Noise interference
4. More than one unit in a group

Check procedure: Check the wiring of interconnecting cables. Check your master and slave addressing when more than one unit is connected in a group.

Central controller: 6845

Description: In this error, miswiring and loose interconnecting cables are involved.

Cause:

1. Loose interconnecting cables
2. Noise interference
3. More than one unit in a group

Check procedure: Check the wiring of interconnecting cables. Check your master and slave addressing when more than one unit is connected in a group.

Central controller: 6846

Description: This error indicates the indoor FTC can’t finish the process or unable to communicate to outdoor Ecodan.

Cause:

1. Loss of or no communication between indoor FTC and outdoor Ecodan.
2. Poor connection of interconnecting cables
3. Not correct 12-24 Vdc fluctuating voltage between S2 and S3

Check procedure:

• First of all, check the voltage on interconnecting cables on S1-S2-S3
• Check continuity on fuses
• Check 240 V supply to indoor FTC and outdoor Ecodan

Central controller: 403

Description: This error indicates the serial communication fault between the Ecodan main control board and the Ecodan power board.

Cause:

1. Loose CN2 or CN5 connection between the two boards
2. Control board failure

Check procedure:

• Check the loose plugs
• Check the voltage

Central controller: 6607

Description: It is not as such a defined error code.

Cause: The main cause is Noise interference

Check procedure: Power down your system and then switch back on.

Description: This code indicates the remote controller transmitting error.

Cause:

1. Incorrect wiring of remote
2. Incorrect dip switch setting if units are grouped

Check procedure:

• If grouped then check unit addressing
• Check remote is wired only to master indoor unit

Description: This code indicates the remote controller issue.

Cause:

1. Faulty controller
2. Poor wiring connection
3. Abnormal voltage to the remote controller

Check procedure: Check the wiring of the remote controller onto the FTC terminals and ensure the 12 Vdc down to the remote control.

Description: It is the remote controller transmitting error.

Cause:

1. Incorrect wiring of the remote
2. Incorrect dip switch setting

Check procedure

• If grouped then check unit addressing
• Check whether the remote is wired to the master unit only

Description: It is the remote controller transmitting error.

Cause:

1. Incorrect wiring of the remote
2. Incorrect dip switch setting

Check procedure:

• If grouped then check unit addressing
• Check whether the remote is wired to the master unit only

Description: It is a remote controller communication error.

Cause:

1. Incorrect wiring of remote
2. If the controller doesn’t have the correct 12 Vdc supply

Check procedure:

• Check for 12 Vdc down to the controller and make sure LED 2 is lit on the FTC board
• Check the SW1 sip switches on the outdoor unit are set correctly

Description: It is again a remote controller transmitting error.

Cause:

1. Remote controller incorrectly wired
2. The controller doesn’t have the correct 12 Vdc supply

Check procedure:

• Check for 12 Vdc down to the controller and make sure LED 2 is lit on the FTC board
• Check the SW1 sip switches on the outdoor unit are set correctly

Central controller: 6840

Description: This indicates the indoor to outdoor communication fault.

Cause:

1. No communication between FTC and outdoor Ecodan
2. Poor connection of interconnecting cables
3. Incorrect supply of 12-24 Vdc fluctuating voltage between S1 and S3

Check procedure:

• Reset power supply first then the outdoor
• Check interconnecting cables and voltage
• Check indoor FTC LEDs
• Power back up the indoor

Description: It is the comms failure indoor to outdoor (S2/S3)

Cause:

1. Miswiring
2. Incorrect system powered up.

Check procedure:

• Check the pumps wired in
• Check the indoor isolator
• Repower indoor,  then outdoor

Central controller: 6841

Description: It is the comms failure indoor to outdoor (S2/S3)

Cause:

1. Miswiring
2. Incorrect system powered up.

Check procedure

• Check the pumps wired in
• Check the indoor isolator
• Repower indoor, then outdoor

Central controller: 4108

Description: This is the error termed as 51 CM connector open circuit

Cause: Thermal relay is an open circuit

Check procedure: Check the thermal relay for disconnection, contact failure, or defective connection.

Central controller: 4103

Description: This is termed reverse-phase detection.

Cause:

1. Causes are as follows:
2. Incorrect power supply
3. Two phases are wrong way round

Check procedure:

• Check power supply
• Try to swap 2 phases round

Central controller: 4102

Description: In this error, the L3 phase opens.

Cause:

1. The main cause is:
2. The power supply is not correct

Check procedure:

• Check power supply
• Check open circuit devices

Central controller: 5202

Description: In this error, lower pressure switch open circuit or incorrect contact to the control board

Cause:

1. The causes are the following:
2. Low-pressure switch detecting low refrigerant pressure in the outdoor unit.
3. The contact of the switch has been damaged.

Check procedure

• Check continuity through the low-pressure switch
• Check the refrigerant gas pressure

Central controller: 4124

Description: This error indicates the 49C open circuit.

Cause:

1. Compressor
2. Inner thermostat
3. Open circuit
4. Contact failure

Check procedure: Check inner thermostat

Central controller: 4118

Description: This error indicates the phase detection circuit failure

Cause:

1. The cause is the power supply phase reversed

Check procedure

• Check power supply
• Swap two phases over

Description: In this error, no input is detected at the outdoor unit

Cause: This is caused due to defective outdoor board

Check procedure: Check whether the main power is ok.

Central controller: 4119

Description: In this error, both the high and low-pressure switches open the circuit.

Cause:

1. Both the high and low-pressure switches open the circuit.
2. Control board fault

Check procedure: Check both the switches and check their connections to the control board.

Description: it represents a room sensor fault.

Cause:

It can be caused by different factors as follows:

1. Faulty thermistor
2. Incorrect sensor setting
3. Loose wiring

Check procedure: Check the thermistor for the circuit and then check the wiring connection.  Also, check the settings of the main controller, Initial setting>Room sensor setting>Sensor settings>Sensor setting, and then change sensing point from TH1 to main R/C.

Description: Indoor liquid pipe thermistor fault. And the PCB detects incorrect temperature reading from the thermistor.

Cause:

1. It is caused due to
2. Faulty thermistor
3. A damaged cable or poor connection to PCB.

Check procedure: Check connection of thermistor on PCB and thermistor wiring.

Central controller: 1302

Description: It is the error indicating Ecodan high-pressure fault.

Cause: It is caused due to the abnormal water flow on the primary circuit.

Check procedure:

• Check flow rate on the sensor
• Check zone valves
• Check water pressure

Central controller: 1102

Description: This is the error of Ecodan high compressor discharge temperature.

Cause:

The main causes are as following :

1. Refrigerant may leak
2. Water flow issue
3. Thermistor detecting abnormally high temperature

Check procedure:

• Check airflow
• Check water flow
• Confirm the dip switch

Central controller: 4250

Description: This is the overcurrent fault

Cause:

1. Compressor issue like winding failure
2. Inverter output failure

Check procedure:

• Measure the resistance of the compressor for a dead circuit
• Carry out an inverter output test