Error codes for the Daikin air conditioner: detection of malfunctions and methods for dealing with them

Air conditioning - a complex unit, consisting of a large number of elements. Even the most advanced equipment, which includes Daikin air conditioning, is not immune to the failure of any of them. In order to quickly identify the causes of malfunctions, manufacturers equip their models with self-diagnosis systems.

Through a combination of letters with numbers and light signals, “smart equipment” informs of all violations in their own work. The display system displays the control panel error codes for the Daikin air conditioner. In case of any malfunction, the corresponding signal starts flashing.

This article introduces the alphanumeric designations of breakdowns, their decoding, causes of occurrence and methods of elimination.

Air conditioner self-diagnosis system

All Daikin air conditioners are equipped with a self-diagnosis system. With its help, they themselves diagnose their condition, and then inform about the problems found. You can run this function in a special mode, but it also works automatically.

Almost all failures can be found by observing the indicators, and the mechanism of this process is very simple. In the normal state, the LEDs emit even light. But as soon as the violation occurred, they begin to pulsate with a subsequent repeat of the flashes. An alphanumeric or alphabetic combination appears on the display of the remote control.

The latest Daikin air conditioners are built with the latest technology. They have a stylish design, low noise, undoubted quality. Models are economical and productive

Having practiced deciphering encoded information about breakdowns, you can understand that some malfunctions can be eliminated by a home craftsman on their own. If the failures are complex, then informing the master of the code, the user will speed up the repair process.

DTC classification

The letter at the beginning of the code indicates the structural part in which the malfunction occurred:

• failure in the internal block - "A", "C";
• failure in the power unit - “E”;
• malfunctions of temperature sensors - "F";
• problems with food - "N";
• malfunctions in the external block - "L";
• fan motors are blocked, drainage pumps are defective, or the electronic board of the indoor unit is “P”;
• system failures - “U”, “M”.

Errors that are not critical and rarely appear are encrypted with a combination of numbers.

Common Daikin air conditioning problems

Most malfunctions of the Daikin air conditioner, especially its indoor unit, are not difficult. Errors shown on the display consist of a classification code (letter) and an error number (number), numbers and letters, two letters.

The control panel is designed to simplify and facilitate the management of air conditioning. There are types of remote control, such as wireless infrared, wall-mounted wired

Not only for different brands, but also for different lines, the codes are slightly different. For this reason, you need to read the instructions. It provides decryption of encoded violations and methods for their elimination.

Indoor unit errors

When the general protective device is activated, the code starts flashing AO. There are many reasons for this:

• overheat compressor;
• failure of fans;
• insufficient amount of refrigerant in the system;
• trash in the capillary tube, another.

Among all the causes, the most difficult is the malfunction of the electronic part. To eliminate it, you need not only a professional tool, but also experience.

Faulty printed circuit board signals a malfunction code A1. As practice shows, the control board is often diagnosed incorrectly. Therefore, before changing it, you need to check the components that most often fail - relays, capacitors.

Among the common reasons for the failure of the control board are only five:

• instability of voltage in the network;
• improper installation of interconnect cables;
• natural wear of individual elements of the board;
• moisture, destructive mechanical stress;
• non-compliance with operating rules.

Often the air conditioner fails due to improper preparation for winter. When the device is de-energized, only the phase is turned off and zero is forgotten. In this case, the electronic board, subject to grounding on a common line, can disable welding work carried out in the neighborhood.

If the air conditioner does not turn on, and all the LEDs blink on the indoor unit, then most likely this is a sign of a malfunction in the software settings of the board. There is only one way out - reprogramming by codes, which can be performed only in the service center

Code A2 signals about blocking of the fan motor. When the self-diagnosis system issues a Daikin air conditioner malfunction code indicating a fan motor failure, you should try to manually rotate the blades. If there is no free rotation, the cause is the wear of the engine bearings, and it will have to be replaced.

The fan motor activates the rotary switch. The contacts inside it corrode over time and stop passing electric current. To make sure that the rotary switch does not conduct electricity, you need to use a multimeter. If the continuity of the switch is confirmed, it must be replaced.

An abnormal level in the drainage system is signaled A3 code. Excess moisture due to improperly arranged condensate drain may cause a breakdown due to a short circuit. In this case, it will be necessary to disassemble the indoor unit and thoroughly clean the drainage system.

If they rotate freely when scrolling fan blades, it is necessary to check the input power to the motor. After making sure that everything is in order with this, and the engine remains inoperative, they come to the conclusion that the engine needs to be changed

A4 codes and A5 indicate malfunction of the heat exchanger and abnormal temperature. This is caused by an error in the temperature sensor.

Check whether this is true, as follows:

1. The temperature sensor is disconnected from the board.
2. Check the resistance on the sensor using special equipment.
3. The measurement result is compared with predetermined values. At a temperature of + 25⁰ on a serviceable sensor, the resistance should be 10 kOhm. If the condition is violated, the sensor is definitely defective and must be replaced.
4. In the event that the measurements showed that the resistance of the sensor meets the standards, it is installed in its place, connected to the board, and the unit itself to the network.
5. Next, check the connector using a multimeter. If the voltage exceeds 4.9 V or is less than 0.5 V, the board must be changed.
6. If the voltage on the connector is normal, the microprocessor is faulty and must be replaced.

When the fan motor is overloaded, the self-diagnosis system issues error code A6. The cause may be a disconnected or broken wire, contact defect, damage to the circuit board.

If replacement of the motor is required, first de-energize the system and dismantle the protective grill. After this, the fan mounts are unscrewed, the electric motor is disconnected and replaced with a new one

Display A7 errors indicates a malfunction of the blinds drive. The motor valve may be defective; check the connections to make sure that nothing is blocking the movement of the blinds.

The most common cause is a motor malfunction. In this case, simply replace it. There is also the possibility of microswitch failure, circuit board malfunction, or connector connection defects.

Such an error as a general overcurrent has code A8. Since the starting current of the compressor motor is much higher than the operating current, the system gives a signal after three seconds after starting the motor.

Overloading can lead to a fire hazard, so you need to start immediately to find out the reasons. This situation can cause a short circuit in the compressor itself.

In this case, the system decides that a fault is present, since the current rises to a significant value. A short circuit can occur outside the compressor - in the control board, on the terminals, in the supply wires.

The cause of error A8 can be an excessive increase in pressure in the discharge system. An increase in this indicator can trigger errors made during refrigerant charging.

The untimely cleaning of the heat exchanger gives the same result. Proper heat transfer can be impeded even by a thin grease film on the surface of a visually clean heat exchanger.

If an error occurs on the compressor current, it is necessary to provide access to it. Next, the air conditioner is started in cooling mode. If the compressor could not be started, the compressor and the connecting wires “ring”. Defective elements or the compressor itself replace

Code A9 indicates a malfunction of the electronic expansion valve. Failure may occur due to mechanical impurities. To check its operation, the power is turned off and then on again. Immediately after power is supplied, the expansion valve should be turned on for 30 s.

During this period, it is determined whether there is a voltage pulse of 12 V in the middle of the diode contacts of the expansion valve. The absence of a pulse indicates a breakdown of the control board.

If there is no cold air, check the sensor for damage. You also need to ring the thermostat contacts with a multimeter both at the lowest and at the highest temperature limit

If, when the fan of the indoor unit is running, the condenser fan stops, the compressor, expansion valve is turned off, the following actions are taken:

• on the control board, the electronic valve contacts are disconnected;
• check if there is a rated voltage on the board.

If a rated voltage is present, this indicates a malfunction of the electronic expansion valve. Lack of voltage indicates a malfunction of the control board.

The error codes of the indoor unit, indicated by the symbol “C”, are summarized in the table:

It cannot be ruled out that a particular malfunction appeared by chance or due to a mismatch of the current parameters in the network to the recommended values

Decryption of the error code, consisting of the spirit of the characters:

There are times when an error covers several technical areas. Then the letter designation of the breakdown does not matter. Master must deal with her

One of the most unpleasant malfunctions is the breakdown of the valves responsible for draining the fluid. It entails the complete replacement of unusable parts.

The table of error codes with double symbols will allow the user to compare the symbols and quickly determine the source of the problem without much difficulty

Before contacting a service center, turn off the household air conditioner for a while, then turn it on again. After reconnecting, the error may not appear. If the code blinks again, you cannot do without a wizard.

Outdoor unit errors

The instructions that came with the air conditioner describe how to eliminate some defects. They can be fully implemented with individual malfunctions of the indoor unit. External side errors and system problems are more complicated, so it’s better to contact the wizard.

Wink EO code indicates the operation of a common protective device. This means that the self-diagnosis device has detected some kind of anomaly.

Work can be broken for several reasons:

• the input connection of the safety device is damaged;
• seat belts are disconnected or broken;
• the shut-off valve is installed in the closed position;
• refrigerant piping clogged;
• the external control board is faulty;
• there was an air short circuit.

Error under code E1 indicates that the printed circuit board of the split control is malfunctioning. When the power supply is turned on E2PROM not working properly.

When the high pressure sensor (HPS) is triggered, error E3. It occurs when the compressor is running while the high pressure switch is on.

The processor of the control board contains the algorithm of the system. From here, the functioning of all its elements is controlled, information from the remote control and sensors is processed, signals are sent, the fan starts

Failure can be caused by an excessively high level of pressure, provoked by a large amount of refrigerant or non-condensable gas.

Other reasons are likely:

• defective high pressure switch;
• disconnection or damage to the bundle of high pressure wires;
• loss of contact in the high-pressure connector;
• PCB damage;
• damage to the refrigerant circuit;
• clogged air filter of the indoor unit;
• clogging of the external heat exchanger;
• malfunction of the outdoor fan in cooling mode.

When the low pressure sensor (LPS) is triggered, E4 code. The compressor is running at this time, and an error occurs when the low pressure switch is activated. The reasons may lie in the malfunctions of the cooler circuit, the low pressure switch may also be malfunctioning.

The low pressure wire connection may disconnect or break. The likelihood of a defect in the connector, the printed circuit board cannot be ruled out. The shut-off valve may remain in the closed position.

If the compressor motor is overloaded, the system signals error E5. It means that the compressor is engaged in thermal protection or the discharge pipe is excessively heated.

A sign of leakage of the cooler is a greasy film on the tubes at the points of entry into the fitting and on the threaded fittings themselves.If such a phenomenon is detected, and short shutdowns occur with the compressor, then the cooler has left the system

Failure can be caused by a malfunction of the shut-off valve, a lack of cooler, damage to the outdoor unit, a malfunction of the 4-way valve or an expansion electronic valve.

Error E6 notifies the compressor engine is blocked by increasing current.

At this time, current protection is triggered due to:

• high pressure level is excessively high;
• voltage drop is observed;
• shut-off valve does not open;
• compressor defective.

Error E7 - the fan motor is blocked due to over current. Failure may be due to a fan malfunction, disconnection from the fan motor or the printed circuit board of the wire bundle or connector. Perhaps it is simply a matter of poor contact or foreign objects stuck in the fan.

With a general current overload occurs error E8. In this case, the input current of the inverter has a value of more than 28 A for 2.5 s. Among the reasons can be noted a compressor failure, a defect in the power transistor, the printed circuit board of both the outdoor and indoor units, and a short circuit.

Error E9 - signal about damage to the expansion electronic valve. It appears when the chain is broken.

The source of E9 error may be a malfunction of the expansion valve or its disconnection, damage to the printed circuit board. The reason may be external - electrical noise

Error under EA code indicates anomalies in the 4-way valve. The origin of the failure:

• poor contact in the connector;
• the thermistor is damaged;
• outdoor unit is defective;
• 4-wire valve coil defective;
• the 4-wire valve is faulty;
• foreign substance mixed with the refrigerant.

EU code indicates an abnormal water temperature due to a malfunction of the outdoor unit or thermistor. On error Ej additional protection is triggered. HER - abnormal moisture level in the drainage system. Ef - The heat storage unit is damaged.

All errors related to nutrition problems go under code "H". BUT - a general sensor defect, indicates a failure of the compressor sensor system. This could be due to bad connections or the circuit board. H1 - Failure of the air temperature sensor. This may be due to a faulty damper or limit switch.

H2 - The system power sensor is defective. H3 - defect in the high pressure sensor. An error appears due to a failure of the high pressure switch, disconnecting the wire bundle, board failure, connector failure.

H4 - defective low pressure sensor. You need to make sure that it is connected. If so, the switch must be checked for integrity. H5 - the compressor does not work, because the overload sensor has tripped. Here you need to look for a defect in the connector or in the compressor motor overload thermistor.

Sensors are devices that allow the unit to work automatically. They are designed to perform measurements of specific technological parameters.

H6 - compressor overload. The compressor itself or the outdoor unit may be defective. An abnormal input voltage or a closed shut-off valve can also cause a failure.

H7 - the fan is overloaded. Possible causes: circuit failure, exit from the connector. When the input voltage sensor is triggered, an error will be indicated under the code H8. Here, the power transistor, gearbox or outdoor unit is allegedly faulty. The internal wiring may be defective.

H9 - Not everything is OK with the outdoor temperature sensor. Indicates that the resistance of the thermostat has exceeded the range of 60-600 kOhm. The external thermistor, the thermistor connector, the printed circuit board may be malfunctioning. Changes in the thermistor resistance are inversely proportional to the change in temperature indicators. The thermistor malfunction is determined using a multimeter.

If codes appeared F0, F1, F2, then the protection worked. In the first case, No. 1 and 2, in the second - No. 1, in the third - No. 3. F3 appears at high temperature of the discharge pipe.

It can be caused by:

• inappropriate cooler volume;
• clogging the pipeline;
• low discharge temperature;
• exit from the thermistor holder;
• disconnecting the expansion valve coil from its body.

Error F6 - excess of the nominal value of the heat exchanger temperature. Clogging of the filter, heat exchanger, fan malfunction, excess refrigerant amount, and the inability to open the shutoff valve lead to such a failure.

A thermistor is the same thermistor, but with a negative temperature coefficient of resistance (TCR). For the manufacture of used metal oxides, ceramics, sometimes even diamond crystals

Code J0 indicates a malfunction of the thermistor. J1, 2, 3 - pressure sensor, current, temperature, respectively. J4 - This is a signal about a sensor defect in the low pressure saturation zone. J5, 6, 7, 8, 9 - malfunctions of the thermistor of the suction pipe, heat exchanger 1 and 2, liquid pipe and gas, respectively.

Errors with the code "L" indicate problems in the inverter system. This can be either the activation of protective devices that turn off the inverter, or transmission errors between the external board and the inverter board. A defect in the printed circuit board and a malfunction of the supply unit give the same effect. You need to try to reboot the system.

If the cooler is insufficient, an error will be displayed P0. Code blinking P1 talks about the imbalance of power supply due to the inconsistency of the voltage between the phases. This may be due to a defect in the capacitor of the main circuit, a malfunction of the magnetic relay, improper wiring of the main circuit.

If the temperature inside the control unit rises, a code will inform P3. The fault is a defect in a thermistor or a printed circuit board. Need to measure resistance. P4, 5, 6 - errors indicating failure of the sensors - power transistor, direct current, output current sensor. P7 indicates a high output current.

Conclusions and useful video on the topic

The following video will demonstrate the process of identifying and eliminating one of the common errors of the air conditioner:

The video will familiarize you with the steps to determine the failure of the control board:

The perfect system of self-diagnosis of the Daikin unit allows you to identify any malfunction promptly. This helps to eliminate errors in the work until the moment when the equipment is completely out of order.

The user must not only decrypt the codes, but also periodically clean the air conditioner. When troubleshooting, repair, depending on complexity, can be performed on site or in a service environment.

In the block below, you can leave a comment with your own impressions of the Daikin air conditioner. Share useful information on the topic of the article, tell us how you determined the error by the coded designation. Ask questions and post photos.