Should there be an error in Panasonic air conditioners, they are deactivated and a light emitting diode starts to blink on the panel. If there is a multi-split system, one needs to read off error codes separately for each inner block. One can decipher Panasonic air error codes with the help of the table provided below. Without ignoring a malfunction message, you do not exacerbate a problem of repairs, which means repairs will not be complex and costly.
Panasonic CS-XE9SKUA air error codes
| Diagnosis display | Abnormality/ Protection control | Abnormality Judgment | Protection Operation | Problem | Check location |
| H00 | No memory of failure | — | Normal operation | — | — |
| H11 | Indoor/outdoor abnormal communication | After operation for 1 minute | Indoor fan only operation can start by entering into force cooling operation | Indoor/outdoor communication not establish (error solution h11) | • Indoor/outdoor wire terminal • Indoor/outdoor PCB • Indoor/outdoor connection wire |
| H12 | Indoor unit capacity unmatched | 90s after power supply | — | Total indoor capability more than maximum limit or less than minimum limit, or number of indoor unit less than two | • Indoor/outdoor connection wire • Indoor/outdoor PCB • Specification and combination table in catalogue |
| H14 | Indoor intake air temperature sensor abnormality | Continuous for 5s | — | Indoor intake air temperature sensor open or short circuit | • Indoor intake air temperature sensor lead wire and connector |
| H15 | Compressor temperature sensor abnormality | Continuous for 5s | — | Compressor temperature sensor open or short circuit | • Compressor temperature sensor lead wire and connector |
| H16 | Outdoor current transformer (CT) abnormality | — | — | Current transformer faulty or compressor faulty | • Outdoor PCB faulty or compressor faulty |
| H19 | Indoor fan motor mechanism lock | Continuous happen for 7 times | — | Indoor fan motor lock or feedback abnormal | • Fan motor lead wire and connector • Fan motor lock or block |
| H23 | Indoor heat exchanger temperature sensor abnormality | Continuous for 5s | — | Indoor heat exchanger temperature sensor open or short circuit | • Indoor heat exchanger temperature sensor lead wire and connector |
| H24 | Indoor heat exchanger temperature sensor 2 abnormality | — | Indoor heat exchanger temperature sensor 2 open or short circuit | • Indoor heat exchanger temperature sensor 2 lead wire and connector | |
| H27 | Outdoor air temperature sensor abnormality | — | Outdoor air temperature sensor open or short circuit | • Outdoor air temperature sensor lead wire and connector | |
| H28 | Outdoor heat exchanger temperature sensor 1 abnormality | — | Outdoor heat exchanger temperature sensor 1 open or short circuit | • Outdoor heat exchanger temperature sensor 1 lead wire and connector | |
| H30 | Outdoor discharge pipe temperature sensor abnormality | — | Outdoor discharge pipe temperature sensor open or short circuit | • Outdoor discharge pipe temperature sensor lead wire and connector | |
| H32 | Outdoor heat exchanger temperature sensor 2 abnormality | — | Outdoor heat exchanger temperature sensor 2 open or short circuit | • Outdoor heat exchanger temperature sensor 2 lead wire and connector | |
| H33 | Indoor! Outdoor Misconnection abnormality | — | — | Indoor and outdoor rated voltage different | • Indoor and outdoor units check |
| H36 | Outdoor gas pipe temperature sensor abnormality | Continuous for 5s | Heating protection operation only | Outdoor gas pipe temperature sensor open or short circuit | • Outdoor gas pipe temperature sensor lead wire and connector |
| H37 | Outdoor liquid pipe temperature sensor abnormality | Cooling protection operation only | Outdoor liquid pipe temperature sensor open or short circuit | • Outdoor liquid pipe temperature sensor lead wire and connector | |
| H38 | Indoor/Outdoor mismatch (brand code) | — | — | Brand code not match | • Check indoor unit and outdoor unit |
| H39 | Abnormal indoor operating unit or standby units | 3 times happen within 40 minutes | — | Wrong wiring and connecting pipe, expansion valve abnormality, indoor heat exchanger sensor open circuit | • Check indoor/outdoor connection wire and connection pipe • Indoor heat exchanger sensor lead wire and connector • Expansion valve and lead wire and connector |
| H59 | ECONAV1 sensor abnormality | Continuous for 25s | — | ECONAVI sensor open or short circuit | • ECONAVI sensor (defective or disconnected) • ECONAVI PCB |
| H64 | Outdoor high pressure sensor abnormality | Continuous for 1 minute | — | High pressure sensor open circuit during compressor stop | • High pressure sensor • Lead wire and connector |
| H97 | Outdoor fan motor mechanism lock | 2 times happen within 30 minutes | — | Outdoor fan motor lock or feedback abnormal | • Outdoor fan motor lead wire and connector • Fan motor lock or block |
| H98 | Indoor high pressure protection | — | — | Indoor high pressure protection (Heating) | • Check indoor heat exchanger • Air filter dirty • Air circulation short circuit |
| H99 | Indoor operating unit freeze protection | — | — | Indoor freeze protection (Cooling) | • Check indoor heat exchanger • Air filter dirty • Air circulation short circuit |
| F11 | 4-way valve Switching abnormality | 4 times happen within 30 minutes | — | 4-way valve switching abnormal | • 4-way valve • Lead wire and connector |
| F17 | Indoor standby units freezing abnormality | 3 times happen within 40 minutes | — | Wrong wiring and connecting pipe, expansion valve leakage, indoor heat exchanger sensor open circuit | • Check indoor/outdoor connection wire and pipe • Indoor heat exchanger sensor lead wire and connector • Expansion valve lead wire and connector |
| F90 | Power factor correction (PFC) circuit protection | 4 times happen within 10 minutes | — | Power factor correction circuit abnormal (error solution f90) | • Outdoor PCB faulty |
| F91 | Refrigeration cycle abnormality | 2 times happen within 20 minutes | — | Refrigeration cycle abnormal | • Insufficient refrigerant or valve close |
| F93 | Compressor abnormal revolution | 4 times happen within 20 minutes | — | Compressor abnormal revolution | • Power transistor module faulty or compressor lock |
| F94 | Compressor discharge overshoot protection | 4 times happen within 30 minutes | — | Compressor discharge pressure overshoot | • Check refrigeration system |
| F95 | Outdoor cooling high pressure protection | 4 times happen within 20 minutes | — | Cooling high pressure protection | • Check refrigeration system • Outdoor air circuit |
| F96 | Power transistor module overheating protection | 4 times happen within 30 minutes | — | Power transistor module overheat | • PCB faulty • Outdoor air circuit (fan motor) |
| F97 | Compressor Overheating protection | 3 times happen within 30 minutes | — | Compressor overheat | • Insufficient refrigerant |
| F98 | Total running current protection | 3 times happen within 20 minutes | — | Total current protection | • Check refrigeration system • Power source or compressor lock |
| F99 | Outdoor direct current (DC) peak detection | Continuous happen for 7 times | — | Power transistor module current protection | • Power transistor module faulty or compressor lock |
Panasonic S-22KA1E5 air error codes
| Outdoor Unit Error Code | Abnormality Control | Areas to verify |
| F27-01 | Indoor / outdoor unit communication line disconnection error | Indoor / outdoor unit communication line, lead wire terminal. |
| F30-01 | Total quantity / capacity of connected indoor unit error | Total quantity / capacity of connected indoor unit is insufficient or over. |
| F30-02 | Noise filter circuit (capacitor) error. | Outdoor unit main PCB. |
| F31-01 | Low pressure protection | Refrigerant cycle, 2 or 3-way valve close, insufficient refrigerant. |
| F31-02 | High pressure protection | Refrigerant cycle, 2 or 3-way valve close, overcharged refrigerant. |
| F31-06 | 4-way valve error | 4-way valve, outdoor unit noise filter PCB, connector CN-HOT. |
| F31-08 | Indoor unit freezing error | Abnormal indoor unit expansion valve. |
| F32-04 | IPM temperature protection | Outdoor unit main PCB. power supply. |
| F32-05 | Total current protection | Compressor locked, refrigerant cyde. |
| F32-06 | Compressor discharge temperature protection | Insufficient refrigerant. |
| F32-08 | PFC protection | Outdoor unit main PCB. |
| F32-09 | DC peak current error | IPM abnormal, compressor locked, compressor lead wire connection, outdoor unit main PCB. |
| F32-10 | Compressor rotation error | |
| F35-02 | Outdoor DC fan motor error | Outdoor DC fan motor, outdoor unit main PCB, connector CN-FM1, CN-FM2. |
| F40-01 | Outdoor temperature sensor error | Outdoor temperature sensor lead wire, outdoor unit main PCB, connector CN-TH1. |
| F40-11 | Compressor suction temperature sensor error | Compressor suction temperature lead wire, outdoor unit main PCB, connector CN-TH2, 3- way valve close. |
| F40-21 | Outdoor heat exchanger temperature sensor error | Outdoor heat exchanger temperature sensor lead wire, outdoor unit main PCB, connector CN-TH1. |
| F40-31 | DEF temperature sensor error | DEF temperature sensor lead wire, outdoor unit main PCB, connector CN-TH2. |
| F40-51 | Compressor discharge temperature sensor error | Compressor discharge temperature sensor lead wire, outdoor unit main PCB, connector CN-DIS. |
| F41-02 | High pressure switch disconnection error | High pressure switch lead wire, outdoor unit main PCB. connector CN-PSW1. |
| F41-12 | Low pressure switch disconnection error | Low pressure switch lead wire, outdoor unit main PCB. connector CN-PSW2. |
| F42-11 | Outdoor CT disconnection error | Outdoor unit main PCB. |
| F44-01 | IPM temperature sensor error | |
| F45-01 | Outdoor address double registration error | Outdoor unit address. |
| F15-01 | Drain level error | Drain pump, float switch, drain pipe, indoor unit main PCB. connector CN-DRMTR. CN-TH2. |
| F17-02 | Indoor DC fan motor error | Indoor DC fan motor, connector CN-FM. |
| F20-01 | Indoor liquid pipe temperature sensor error | Indoor liquid pipe temperature sensor lead wire, indoor unit main PCB. connector CN-TH2. |
| F20-02 | Remote control thersistor error | Remote control thermistor. |
| F21-01 | Indoor heat exchanger temperature sensor error | Indoor heat exchanger temperature sensor lead wire, indoor unit main PCB. connector CN-TH1. |
| F22-01 | Indoor gas pipe temperature sensor error | Indoor gas pipe temperature sensor lead wire, indoor unit main PCB. connector CN-TH1. |
| F25-01 | Indoor address double registration error | Indoor unit address. |
| F26-01 | Remote control communication line disconnection error | Remote control lead wire, terminal, indoor unit main PCB connector CN-REM. |
| F27-01 | Indoor / outdoor unit communication line disconnection error | Indoor / outdoor unit communication lead wire, connection terminal, indoor unit main PCB connector CN-UN, outdoor unit address. |
| F31-08 | Indoor unit freezing error. | Abnormal indoor unit expansion valve, indoor unit heat exchanger sensor. |
Panasonic S-45PU1E5 air error codes
| Alarm/ Code | Alarm Meaning |
| E01 | Remote Controller Reception Error |
| E02 | Remote Controller Transmission Error |
| E03 | Error in Indoor Unit Receiving Signal from Remote Controller (central) |
| E04 | Error in Indoor Unit Receiving Signal from the Outdoor unit |
| E05 | Error in Indoor Unit Transmitting Signal to the Outdoor Unit |
| E06 | Outdoor Unit Failed to Receive Serial Communication Signals from Indoor Unit |
| E07 | Outdoor Unit Sending Failure to Indoor Unit |
| E08 | Duplicate Indoor Unit Address Settings Error |
| E09 | More Than One Remote Controller Set to Main Error |
| E12 | Automatic Address Setting Start is Prohibited while Auto-address Setting in Progress. |
| E13 | Error in Indoor Unit Transmitting Signal to Remote Controller |
| E14 | Main Unit duplication in Simultaneous-operation Multi Control (detected outdoor unit) |
| E15 | Automatic Address Alarm (capacity too low) |
| E16 | Automatic Address Alarm (capacity too high) |
| E18 | Faulty Communication in Group Control Wiring |
| E20 | No Indoor Units Connected |
| F04 | Compressor Discharge Temperature Sensor (TD) Trouble |
| F06 | Inlet Temperature Sensor (C1) in Heat Exchanger Trouble |
| F07 | Intermediate Temperature Sensor (C2) in Heat Exchanger Trouble |
| F08 | Outdoor Air Temperature Sensor (TO) Trouble |
| F12 | Compressor Inlet Suction Temperature Sensor (TS) Trouble |
| F31 | Outdoor Unit Nonvolatile Memory (EEPROM) Trouble |
| H01 | Primary (input) Overcurrent Detected |
| H02 | PAM Trouble |
| H03 | Primary Current CT Sensor (current sensor) Failure |
| H05 | Sensor Failure. Compressor Discharge Temperature Sensor (TD) Disconnected |
| H31 | HIC Trouble |
| L04 | Outdoor Unit Address Duplication |
| L10 | Outdoor Unit Capacity not Set |
| L13 | Indoor Unit Type Setting Error |
| L18 | 4-way Valve Operation Failure |
| P03 | Compressor Discharge Temperature Trouble |
| P04 | High Pressure Trouble |
| P05 | AC Power Supply Trouble |
| P13 | Alarm Valve Open |
| P14 | 02 Sensor Detect |
| P15 | Insufficient Gas Level Detected |
| P16 | Compressor Overcurrent Trouble |
| P22 | Outdoor Unit Fan Motor Trouble |
| P29 | Lack of INV Compressor Wiring, INV Compressor Actuation Failure (including locked) due to DCCT Failure |
Panasonic U-36LE1U6 air error codes
| Alarm code | E06 |
| Alarm meaninq | Outdoor unit failed to receive serial communication siqnals from indoor unit. |
| Alarm conditions | No serial communications from indoor unit |
| Probable cause | (1) The indoor unit power was cut OFF after initial communications were completed. (2) An open circuit or short circuit occurred in the inter-unit control wiring after initial communications were completed. |
| Check | Check the power at the indoor and outdoor units, and check the inter-unit control wirinq. |
| Notes | This alarm is detected after initial communications are completed. Therefore, it does not occur in cases of ‘disconnected serial connector V no terminal unit set, or other trouble that occurs before initial communications are completed. If initial communications have not been completed, alarm E04 occurs. |
| Alarm code | E12 |
| Alarm meaning | Automatic address setting start is prohibited. |
| Alarm conditions | Automatic address setting was started when automatic address setting was in progress at another outdoor unit in the same link. |
| Probable cause | Automatic address setting is in progress at another outdoor unit. |
| Check | This alarm is not displayed on the remote controller. Therefore check the blinking LED display on the outdoor unit PCB. |
| Correction | Wait for automatic address setting to be completed at the outdoor unit where it is currently in progress. Then start automatic address setting again. |
| Alarm code | E15 |
| Alarm meaninq | Automatic address settinq alarm (too few units) |
| Alarm conditions | The number of indoor units was too few when automatic address setting was performed. |
| Probable cause | (1) The number of indoor units set at the indoor unit quantity setting SW (S004) on the outdoor unit PCB is too many. (2) The inter-unit control wiring between indoor units has been cut. |
| Check | (1) check the indoor unit quantity setting SW (S004). (2) Check the inter-unit control wiring at the indoor and outdoor units. |
| Correction | After correcting the indoor unit quantity setting or the inter-unit control wiring, perform automatic address setting again. |
| Alarm code | E16 |
| Alarm meaninq | Automatic address settinq alarm (too many units) |
| Alarm conditions | • The number of indoor units was too many when automatic address setting was performed. • After initial communications were completed, an unrecognized unit was detected. |
| Probable cause | (1) The number of indoor unit setting SW (S004) on the outdoor unit PCB is too small. (2) The inter-unit control wiring is wired incorrectly. |
| Check | (1) check the number of indoor units that is set. (2) Check the inter-unit control wirinq at the indoor and outdoor units. |
| Correction | After correcting the indoor unit quantity setting or the inter-unit control wiring, perform automatic address setting again. |
| Alarm code | E20 |
| Alarm meaninq | No indoor units at automatic address settinq. |
| Alarm conditions | When automatic address settinq was performed, no indoor units were recoqnized. |
| Probable cause | (1) The inter-unit control wiring from the outdoor unit to the indoor units has been cut. (2) Serial connector 1 (CN32) is disconnected at the outdoor unit. (3) The power is OFF at all indoor units in the system. |
| Check | (1) Check whether the inter-unit control wiring from the outdoor unit to the indoor units is cut. (2) Check whether serial connector 1 (CN32) is disconnected at the outdoor unit. (3) Check the power at the indoor units. |
| Correction | (1) Repair inter-unit control wiring from outdoor / indoor units. (2) Plug connector 1 (CN32) in correctly. (3) Turn on the power to indoor units. |
| Alarm code | E25 |
| Alarm meaning | Outdoor unit address setting failure (duplication) |
| Alarm conditions | Communication by outdoor unit main-sub control wiring was received that contained the same address as that unit 5 times or more within 3 minutes. |
| Probable cause | The unit number is set incorrectly. |
| Check | Check the unit number again. |
| Correction | Correct the incorrect unit number setting. |
| Notes | Recovery from this alarm occurs automatically (when communication that contains the same address is not received for 3 minutes). |
| Alarm code | F04 |
| Alarm meaning | Compressor 1 discharge temperature sensor trouble |
| Alarm conditions | (1) A temperature of 212°F (100°C) or higher was detected 20 minutes or longer after that compressor stopped running. (2) Temperature is 176°F (80°C) or higher when the outdoor unit has been stopped for 60 minutes or longer. Details are given in the servicing technical materials. (3) A/D step is 10 steps or less (short circuit). |
| Probable cause | (1) Sensor malfunction • Sensor element malfunction • Sensor wiring is partially disconnected, resulting in increased electrical resistance. • This alarm does not occur when the wiring is completely cut or when the connector is not connected to the outdoor unit PCB. (2) Outdoor unit PCB failure (3) An air short blockage in the area around the outdoor unit has increased the outdoor unit ambient temperature, reducing the cooling effects after the compressor stops. (4) There is a cause that results in P03 alarm. (5) Electrical noise |
| Check | (1) Sensor malfunction and outdoor unit PCB failure Trouble: • Constantly indicates a high temperature. • When monitoring software or other means are used for monitoring, the discharge temperature at times fluctuates suddenly and wildly. • In some cases, the precise temperature may not be known, even when monitoring software is used. Check: • Wiggle the sensor and check whether the trouble continues. • Check whether the connector is partially disconnected from the PCB. • An F04 alarm will not result if the connector is completely disconnected (circuit is open). (2) Leakage from the discharge tube check valve Trouble: Although the other compressor is operating and this compressor is stopped, the discharge temperature of this compressor rises together with the temperature of the other compressor. (3) If the cause is still unknown after checking the above, then it is possible that electrical noise is the cause of the trouble. It is necessary to provide a line filter or carry out other noise countermeasures. |
| Correction | (1) Replace the sensor. (2) Carry out noise countermeasures. (3) Adjust the amount of refrigerant. (4) Correct the trouble. |
| Example | (1) Sensor wirinq is partially cut. |
| Notes | This alarm does not indicate that the sensor is disconnected. In order to prevent overheating during operation, the outdoor units in this system will not allow a compressor to start if the discharge temperature does not decrease while the compressor is stopped. If a sensor malfunction results in continuous detection of a high discharge temperature, then the compressor may stop for no apparent reason. The purpose of this alarm is to facilitate identification of the problem in this case. |
| Alarm code | F07 |
| Alarm meaning | Liquid temperature sensor (C1) trouble at outdoor heat exchanger |
| Alarm conditions | (1) A/D step is 10 steps or less (short circuit). (2) A/D step is 1014 steps or more (open circuit). |
| Probable cause | (1) Sensor malfunction (including connector) (2) PCB malfunction |
| Check | (1) Measure the sensor resistance. Check that the sensor is operating normally. (2) Use a remote controller monitor or PC monitor to check the temperature that is recognized by the microcomputer. |
| Alarm code | F08 |
| Alarm meaning | Outdoor air temperature sensor trouble |
| Alarm conditions | (1) A/D step is 10 steps or less (short circuit). (2) A/D step is 1014 steps or more (open circuit) |
| Probable cause | (1) Sensor malfunction (including connector) (2) PCB malfunction |
| Check | (1) Measure the sensor resistance. Check that the sensor is operating normally. (2) Use a remote controller monitor or PC monitor to check the temperature that is recognized by the microcomputer. |
| Alarm code | F12 |
| Alarm meaning | Compressor intake temperature sensor trouble |
| Alarm conditions | (1) A/D step is 10 steps or less (short circuit). (2) A/D step is 1014 steps or more (open circuit) |
| Probable cause | (1) Sensor malfunction (including connector) (2) PCB malfunction |
| Check | (1) Measure the sensor resistance. Check that the sensor is operating normally. (2) Use a remote controller monitor or PC monitor to check the temperature that is recognized by the microcomputer. |
| Alarm code | F16 |
| Alarm meaning | High-pressure sensor trouble |
| Alarm conditions | The saturation temperature at the detected pressure is 10 °F (5 °C) or more below the highest indoor-unit E1 temperature continuously for 30 minutes. |
| Probable cause | (1) High-pressure sensor malfunction (2) Failure to connect the connector to the outdoor unit PCB (3) Failure to open the service valve (4) Clogged tubing (5) Valve leakage (6) Over-charging (7) Outdoor unit PCB failure (8) Electrical noise |
| Check | (1) High-pressure sensor failure • Check for cut wiring. • Connect a gauge to the high-pressure pressure outlet and check for changes in the value displayed by the monitoring software, and for large deviation of the gauge pressure. • During heating, check whether the temperature is lower than the highest indoor-unit E1 temperature. • The pressure detected by the high-pressure sensor is the highest pressure in the system. Therefore during heating the converted saturation temperature will never be lower than any indoor-unit E1 temperature. During cooling this temperature will never be lower than the outdoor unit liquid temperature. (2) Failure to open the service valve, clogged tubing, valve leakage, over-charging. In all of these cases, an alarm occurs when there are rapid pressure fluctuations and tracking of the detected pressure is poor. • Check the open/closed status of the valve. • Check for valve leakage and over-charging When valve leakage or over-charging occurs, refrigerant is likely to accumulate in the outdoor units or indoor units, resulting in a sudden rise in pressure at start that occurs before the refrigerant in the heat exchanger is discharged. • The representative valve to check is a mechanical valve. (3) Outdoor unit PCB failure • The check items are the same as for a high-pressure sensor malfunction. A normal PCB is needed to determine whether the problem is a PCB failure or a pressure sensor malfunction. If an abnormality was found at the check items for a high-pressure sensor malfunction, first try replacing the PCB and check again. Trouble is corrected : Outdoorunit PCB failure Trouble is not corrected : High-pressuresensor malfunction |
| Correction | (1) Replace the high-pressure sensor. Caution: Because the high-pressure sensor connection incorporates a Schrader-type valve, it can be removed and replaced. However, the high-pressure sensor can be easily damaged by high voltage; therefore use sufficient caution with regard to static electricity. (2) Replace the PCB. (3) Correct the locations of problems in the refrigeration cycle. • Correct locations where clogging or leakage has occurred. • In the case of over-charging, recover refrigerant. (Adjust the amount of refrigerant). |
| Example | This alarm may result when the service valve is closed or when valve leakage (particularly from the mechanical valve) occurs. |
| Alarm code | F31 |
| Alarm meaning | Outdoor unit non-volatile memory (EEPROM) trouble |
| Alarm conditions | (1) Non-volatile memory is not present when power initialization occurs. (2) Read values do not match after writing to non-volatile memory is complete. |
| Probable cause | (1) Memory was not inserted after the PCB was replaced. (2) The lifetime of the non-volatile memory has been reached. (3) Non-volatile memory is installed incorrectly (wrong direction, bent pins, etc.). |
| Check | (1) Check the non-volatile memory on the PCB. |
| Alarm code | H03 |
| Alarm meaning | Compressor CT sensor disconnected or short-circuit |
| Alarm conditions | Alarm occurs if the current value is 1.5 A or less when 2 seconds or longer have elapsed after output from that compressor started. • No current is detected even though the compressor is operating. |
| Probable cause | (1) CT circuit failure (including cut wiring, etc.) (2) Disconnected CT circuit connector (3) This CT circuit is connected to the connector of the other CT circuit. (4) PCB failure (5) Noise |
| Check | (1) CT circuit failure. PCB failure Trouble: • Current value during compressor operation is below the threshold value. Check: • Check that the connector is not disconnected. • Check the continuity of the CT circuit. • Install a normal CT in place of this CT and check. If current is detected, then the PCB can be judged OK. • CT circuit failure • Check that current is flowing in the phase where the CT circuit is connected. • Check voltage and current. (2) Crossed wiring or installation error Trouble: When the compressor is stopped, the current value at the other compressor is high. (3) If the cause is still unknown after checking the above, then it is possible that noise is the cause of the trouble. It is necessary to connect a PC or other instrument. |
| Correction | (1) Replace the CT circuit. (2) Replace the outdoor unit PCB. (3) Correct the problem. |
| Example | (1) The connector was not inserted after the PCB was replaced. |
| Notes | Use a normal CT as a tool to determine whether the trouble is a PCB failure or CT failure. |
| Alarm code | L05 |
| Alarm meaninq | Indoor unit priority duplication (at priority indoor units) |
| Alarm conditions | More than 1 indoor unit set for priority was detected. |
| Probable cause | More than 1 indoor unit is set for priority. |
| Check | From the wired remote controller, use the indoor unit EEPROM simple setting mode and check that the value of item code 04 is 0001 |
| Correction | Use the wired remote controller and correct the setting if the value of indoor EEPROM item code 04 is incorrect. |
| Notes | This alarm is displayed at the indoor units that are set for priority. Alarm L06 is displayed at the indoor units that are not set for priority. |
| Alarm code | L06 |
| Alarm meaninq | Indoor unit priority duplication (at non-priority indoor units) and outdoor unit |
| Alarm conditions | More than 1 indoor unit set for priority was detected in the system. |
| Probable cause | More than 1 indoor unit is set for priority in the system. |
| Check | Find the indoor units where alarm L05 has occurred in the system. |
| Correction | |
| Notes | Alarm L06 occurs as a result of alarm L05. When the duplicated priority settings are corrected, alarm L06 is also corrected. |
| Alarm code | L10 |
| Alarm meaning | Outdoor unit capacity not set |
| Alarm conditions | The outdoor unit capacity has not been set, or the setting is not allowed by the system. |
| Probable cause | This alarm occurs because the capacity has not been set. |
| Check | Connect the outdoor unit maintenance remote controller. On the outdoor unit EEPROM detailed setting mode screen, check the value for the outdoor unit capacity (item code 81). Check that it is not set to “O” or to a capacity that is not allowed. |
| Correction | If item code 81 is incorrect, use the outdoor unit maintenance remote controller and set it correctly. • After chanqinq the settinq. be sure to reset both the indoor and outdoor power. |
| Notes | The outdoor unit maintenance remote controller is required in order to set the capacity in the outdoor unit EEPROM. |
| Alarm code | L18 |
| Alarm meaning | 4-way valve operation failure |
| Alarm conditions | During heating, when 2 minutes and 30 seconds have elapsed after compressor operation started, the temperature difference between the outdoor air temperature sensor and the heat exchanger liquid temperature sensor (C1) is 40 °F (20 °C) or higher. |
| Probable cause | (1) The 4-way valve connector (20S CN005) has become disconnected from the control PCB. (2) The 4-way valve circuit is locked (malfunctioning). |
| Check | (1) Check the 4-way valve connector (20S CN005). (2) If the connector is normal, check the 4-way valve wiring and the PCB circuit. |
| Correction | If the connector is normal, correct or replace the problem locations. |
| Alarm code | P03 |
| Alarm meaning | Compressor discharge temperature trouble |
| Alarm conditions | Inverter compressor: Temperature is 222 °F (106 °C) or higher and pre-trip stop has occurred. |
| Probable cause | (1) Insufficient amount of refrigerant (including trouble resulting from an insufficient initial charge and from gas leakage) Blocking of low-pressure parts caused by intrusion of foreign objects (moisture, scale, etc.) (2) Expansion valve operation failure (3) Compressor discharge sensor failure (4) PCB failure (A/D conversion failure) (5) Electrical noise |
| Check | (1) Insufficient refrigerant Trouble: Liquid effectiveness is poor. Check: Check whether or not the superheating temperature is declining if the evaporator mechanical valve is opened to 300 pulses or more (after checking for foreign object intrusion). (2) Sensor failure Check: • This alarm is likely to occur when wiring is partially cut. (It can be difficult to identify, even when conductivity is checked.) The detected discharge temperature is high. • Although such conditions rarely occur, a P02 alarm is likely if the detected discharge temperature is low. • Replace the sensor with another discharge sensor and compare the temperature conditions. (3) If the cause is still unknown after checking the above, then it is possible that electrical noise is the cause of the trouble. |
| Correction | (1) Replace the sensor. (2) Replace the outdoor unit PCB. (3) Correct the problem locations. |
| Example | All of the probable causes |
| Notes | Operates continuously for a set length of time. Indicates 2 minutes 30 seconds or longer for an inverter unit. |
| Alarm code | P16 |
| Alarm meaning | Inverter compressor overcurrent alarm |
| Alarm conditions | This alarm occurs when current trouble or current detection trouble occurs at an inverter frequency of less than 80 Hz after start (when trouble judgment current is detected in the primary or secondary current, or when an instantaneous secondary current of 48 A or hiqher is detected). |
| Probable cause | There is a strong possibility of a compressor failure. |
| An alarm occurs for current detection trouble when it is judged that no current is flowing after start (DCCT is damaqed). In this case, the cause is a DCCT failure. | |
| Check | Check the power wirinq and connector wirinq. |
| Correction | It is possible to resolve this trouble by limitinq the maximum frequency. |
| Alarm code | P22 |
| Alarm meaning | Fan motor trouble |
| Alarm conditions | Fan motor start failure, fan motor Hybrid IC input failure |
| Probable cause | Possible causes are a Hybrid IC input circuit failure or a fan HIC failure. |
| Check | Check the fan motor wiring, the Hybrid IC wiring, and the connector connections. If the wiring and connectors are normal, then check that the capacitor of the Hybrid IC input circuit is securely soldered onto the PCB. Also use a tester and measure the resistance between fan HIC power (HIC+) and ground (HIC-). If there is a short circuit, there is an HIC malfunction. |
| Correction | If the fan does not start, the below corrections may be effective. (1) If there is a fan HIC failure or circuit failure, replace the PCB. (2) If the fan motor is locked, replace the fan motor. |
| Notes | Turn OFF the power, and check the conductivity of V and on the main PCB. |
| Alarm code | P26 |
| Alarm meaning | Inverter compressor high-frequency overcurrent alarm |
| Alarm conditions | This alarm occurs when current trouble or current detection trouble occurs at an inverter frequency of 80 Hz or higher after start (when trouble judgment current is detected in the primary or secondary current, or when an instantaneous secondary current of 48 A or higher is detected). |
| Probable cause | The detection methods are the same as for P16. However the fact that operation up to high frequencies is possible does not necessarily mean that a compressor failure is the cause of the trouble. Start the compressor several times. If alarm P26 occurs every time and alarm P16 does not occur at all, then the possibility of a compressor failure is low. |
| Check | Check the power wiring and connector wiring. |
| Correction | It is possible to resolve this trouble by limiting the maximum frequency. |
| Alarm code | P29 |
| Alarm meaning | Inverter compressor missing phase or lock alarm |
| Alarm conditions | This alarm may occur at start, and occurs when missing phase or lock is detected, and when a DCCT failure occurs. |
| Probable cause | Generally this alarm occurs when the refrigerant pressure balance is uneven at start, when inverter compressor lock occurs, there is a missing phase in the inverter compressor wiring, or a DCCT failure occurs. This can be judged to be starting trouble which is not caused by HIC. |
| Check | Check the power wiring and connector wiring. |
| Correction | DCCT failure (replace PCB) or compressor failure |
| Notes | Use a tester to measure the voltage between the DCCT output terminal on the rear of the PCB and the ground. If the voltaqe is not within 2 – 3 V. then the DCCT has malfunctioned. |
Panasonic U-72MF1U9 air error codes
| Alarm code | Alarm meaning |
| E06 | Outdoor unit failed to receive serial communication siqnals from indoor unit. |
| E12 | Automatic address settinq start is prohibited. |
| E15 | Automatic address settinq alarm (too few units) |
| E16 | Automatic address setting alarm (too many units) |
| E20 | No indoor units at automatic address setting. |
| E24 | Outdoor unit (INV) failed to receive communications from another outdoor unit (constant-speed). |
| E25 | Outdoor unit address settinq failure (duplication) |
| E26 | Mismatch in outdoor unit quantity |
| E29 | Outdoor unit failed to receive communication from relay control unit |
| F04 | Compressor 1 discharge temperature sensor trouble |
| F05 | Compressor 2 discharge temperature sensor trouble |
| F06 | Gas temperature sensor trouble at outdoor heat exchanger 1 (In) |
| F07 | Liquid temperature sensor trouble at outdoor heat exchanqer 1 (Out) |
| F08 | Outdoor air temperature sensor trouble |
| F12 | Compressor intake temperature sensor trouble |
| F16 | High-pressure sensor trouble |
| F17 | Low-pressure sensor trouble |
| F23 | Gas temperature sensor trouble at outdoor heat exchanqer 2 (In) |
| F24 | Liquid temperature sensor trouble at outdoor heat exchanqer 2 (Out) |
| F31 | Outdoor unit non-volatile memory (EEPROM) trouble |
| H03 | Compressor 1 CT sensor disconnected or short-circuit. |
| H11 | Constant speed compressor 2 over current alarm (error solution h11) |
| H12 | Constant speed compressor 2 lock current alarm |
| H06 | Low-pressure trouble in refrigerant circuit. |
| H07 | No oil alarm |
| H08 | Compressor 1 oil detection sensor (connection) trouble |
| H13 | Compressor 2 CT sensor disconnected or short-circuit |
| H15 | Compressor 2 discharge temperature sensor disconnected |
| H27 | Compressor 2 lock current alarm |
| H31 | HIC trouble alarm |
| L04 | Outdoor unit address duplication |
| L10 | Outdoor unit capacity not set |
| L17 | Outdoor unit model mismatch |
| P03 | Compressor 1 discharge temperature trouble |
| P04 | High-pressure switch activated |
| P05 | Reverse phase (or missinq phase) detected |
| P16 | Compressor 1 over current |
| P17 | Compressor 2 discharge temp trouble |
| P22 | Fan motor trouble |
| P26 | Inverter compressor hiqh-frequency over current alarm |
| P29 | Inverter compressor missinq phase or lock alarm |
Panasonic WH-MDC05F3E5 air fault codes
| Diagnosis display | Abnormality/Protection control | Abnormality judgement | Primary location to verify |
| H00 | No abnormality detected | — | — |
| H12 | Indoor/Outdoor capacity unmatched | 90s after power supply | • Indoor/outdoor connection wire • Indoor/outdoor PCB • Specification and combination table in cataloque |
| H15 | Outdoor compressor temperature sensor abnormality | Continue for 5 sec. | • Compressor temperature sensor (defective or disconnected) |
| H20 | Water pump abnormality | Continue for 10 sec. | • Indoor PCB |
| • Water pump (malfunction) | |||
| H23 | Indoor refrigerant liquid temperature sensor abnormality | Continue for 5 sec. | • Refrigerant liquid temperature sensor (defective or disconnected) |
| H27 | Service valve error | Continue for 5 minutes | • High pressure sensor (defective or disconnected) |
| H42 | Compressor low pressure abnormality | — | • Outdoor pipe temperature sensor • Clogged expansion valve or strainer • Insufficient refrigerant • Outdoor PCB • Compressor |
| H62 | Water flow switch abnormality | Continue for 1 min. | • Water flow switch |
| H64 | Refrigerant high pressure abnormality | Continue for 5 sec. | • Outdoor high pressure sensor (defective or disconnected) |
| H65 | Deice circulation error | Continue for 10 sec. | • Water flow switch sensor (defective or disconnected) • Water pump malfunction • Buffer tank (is used) |
| H70 | Back-up heater OLP abnormality | Continue for 60 sec. | • Back-up heater OLP (Disconnection or activated) |
| H72 | Tank sensor abnormal | Continue for 5 sec. | • Tank sensor |
| H76 | Indoor – control panel communication abnormality | — | • Indoor – control panel (defective or disconnected) |
| H90 | Indoor/outdoor abnormal communication | > 1 min after starting operation | • Internal/external cable connections • Indoor/Outdoor PCB |
| H91 | Tank heater OLP abnormality | Continue for 60 sec. | • Tank heater OLP (Disconnection or activated) |
| H95 | Indoor/Outdoor wronq connection | — | • Indoor/Outdoor supply voltaqe |
| H98 | Outdoor high pressure overload protection | — | • Outdoor high pressure sensor • Water pump or water leakage • Clogged expansion valve or strainer • Excess refrigerant • Outdoor PCB |
| H99 | Indoor heat exchanger freeze prevention | — | • Indoor heat exchanger • Refriqerant shortaqe |
| F12 | Pressure switch activate | 4 times occurrence within 20 minutes | • Pressure switch |
| F14 | Outdoor compressor abnormal revolution | 4 times occurrence within 20 minutes | • Outdoor compressor |
| F15 | Outdoor fan motor lock abnormality | 2 times occurrence within 30 minutes | • Outdoor PCB • Outdoor fan motor |
| F16 | Total running current protection | 3 times occurrence within 20 minutes | • Excess refrigerant • Outdoor PCB |
| F20 | Outdoor compressor overheating protection | 4 times occurrence within 30 minutes | • Compressor tank temperature sensor • Clogged expansion valve or strainer • Insufficient refrigerant • Outdoor PCB • Compressor |
| F22 | I PM (power transistor) overheating protection | 3 times occurrence within 30 minutes | • Improper heat exchange • I PM (Power transistor) |
| F23 | Outdoor Direct Current (DC) peak detection | 7 times occurrence continuously | • Outdoor PCB • Compressor |
| F24 | Refrigeration cycle abnormality | 2 times occurrence within 20 minutes | • Insufficient refrigerant • Outdoor PCB • Compressor low compression |
| F25 | Cooling/Heating cycle changeover abnormality | 4 times occurrence within 30 minutes | • 4-way valve • V-coil |
| F27 | Pressure switch abnormality | Continue for 1 min. | • Pressure switch |
| F30 | Water outlet sensor 2 abnormality | Continue for 5 sec. | • Water outlet sensor 2 (defective or disconnected) |
| Diagnosis display | Abnormality/Protection control | Abnormality judgement | Primary location to verify |
| F36 | Outdoor air temperature sensor abnormality | Continue for 5 sec. | • Outdoor air temperature sensor (defective or disconnected) |
| F37 | Indoor water inlet temperature sensor abnormality | Continue for 5 sec. | • Water inlet temperature sensor (defective or disconnected) |
| F40 | Outdoor discharge pipe temperature sensor abnormality | Continue for 5 sec. | • Outdoor discharge pipe temperature sensor (defective or disconnected) |
| F41 | PFC control | 4 times occurrence within 10 minutes | • Voltage at PFC |
| F42 | Outdoor heat exchanger temperature sensor abnormality | Continue for 5 sec. | • Outdoor heat exchanger temperature sensor (defective or disconnected) |
| F43 | Outdoor defrost sensor abnormality | Continue for 5 sec. | • Outdoor defrost sensor (defective or disconnected) |
| F45 | Indoor water outlet temperature sensor abnormality | Continue for 5 sec. | • Water outlet temperature sensor (defective or disconnected) |
| F46 | Outdoor Cunent Transformer open circuit | — | • Insufficient refrigerant |
| • Outdoor PCB | |||
| • Compressor low | |||
| F48 | Outdoor EVA outlet temperature sensor abnormality | Continue for 5 sec. | • Outdoor EVA outlet temperature sensor (defective or disconnected) |
| F49 | Outdoor bypass outlet temperature sensor abnormality | Continue for 5 sec. | • Outdoor bypass outlet temperature sensor (defective or disconnected) |
| F95 | Cooling high pressure overload protection | — | • Outdoor high pressure sensor • Water pump or water leakage • Clogged expansion valve or strainer • Excess refrigerant • Outdoor PCB |