Panasonic air conditioners are widespread, because they possess not only a good set of functions, but offer their users a range of automatically controlled systems. One of them is represented by the error codes` system. It can be seen below in form of a chart, where error codes decoding is given.
Panasonic CS-S9PKR air conditioner error codes
Panasonic CS-S9PKR is a cooling only inverter air conditioner. Its power equals 2.6 kW. The model boasts a high level of energy efficiency, a built-in anti-bacterial filter and dehumidifier. The AC has intuitive controls, so it is comparatively easy to set up. In addition to this, the company emphasizes that this model is characterized by very quiet operation.
Diagnosis display | Abnormality / Protection control | Problem | Check location |
---|---|---|---|
H00 | No memory of failure | — | — |
H11 | Indoor/outdoor abnormal communication | I ndoor/outdoor communication not establish | Indoor/outdoor wire terminal Indoor/outdoor PCB Indoor/outdoor connection wire |
H12 | Indoor unit capacity unmatched | 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 | Indoor intake air temperature sensor open or short circuit | Indoor intake air temperature sensor lead wire and connector |
H15 | Compressor temperature sensor abnormality | 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 merchamsm lock | 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 | Indoor heat exchanger temperature sensor open or short circuit | Indoor heat exchanger temperature sensor 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 |
H34 | Outdoor heat sink temperature sensor abnormality | Outdoor heat sink temperature sensor open or short circuit | Outdoor heat sink sensor |
H36 | Outdoor gas pipe temperature sensor abnormality | 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 | 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 | Wrong wiring and connecting pipe, expansion valve abnormality, indoor heat exchanger sensor open circuit | Check mdoor/outdoor connection wire and connection pipe Indoor heat exchanger sensor lead wire and connector Expansion valve and lead wire and connector |
H41 | Abnormal wiring or piping connection | Wrong wiring and connecting pipe, expansion valve abnormality | Check mdoor/outdoor connection wire and connection pipe Expansion valve and lead wire and connector. |
H59 | ECO patrol sensor abnormality | ECO patrol sensor open or short circuit | ECO patrol sensor ECO patrol and Indoor PCB |
H64 | Outdoor high pressure sensor abnormality | High pressure sensor open circuit during compressor stop | High pressure sensor Lead wire and connector |
H97 | Outdoor fan motor mechanism lock | 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-way valve switching abnormal | 4-way valve Lead wire and connector. |
F17 | Indoor standby units freezing abnormality | 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 | Power factor correction circuit abnormal | Outdoor PCB faulty |
F91 | Refrigeration cycle abnormality | Refrigeration cycle abnormal | Insufficient refrigerant or valve close |
F93 | Compressor abnormal revolution | Compressor abnormal revolution | Power transistor module faulty or compressor lock |
F94 | Compressor discharge pressure overshoot protection | Compressor discharge pressure overshoot | Check refrigeration system |
F95 | Outdoor cooling high pie»»uie piuteUiun | Cooling high pressure piuleUiun | Check refrigeration system Oulduui aii uiuiit |
F96 | Power transistor module overheating protection | Power transistor module overheat | PCB faulty Outdoor air circuit (fan motor) |
F97 | Compressor overheating protection | Compressor overheat | Insufficient refrigerant |
F98 | Total running current protection | Total current protection | Check refrigeration system Power source or compressor lock |
F99 | Outdoor direct current (DC) peak detection | Power transistor module current protection | Power transistor module faulty or compressor lock |
Panasonic R410A air conditioner error codes
Panasonic R410A is a range of air conditioners using the R410A refrigerant. It is an older type of refrigerant. Although it has a zero ozone depletion capacity, it cannot be considered ecology-friendly due to its high global warming potential (2088). It therefore can’t compete with R-290 or R-600A refrigerants, whose global warming potential is only 3.
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 S-36PU1E5A air conditioner error codes
Panasonic S-36PU1E5A range comprises air conditioning systems that may have several types of indoor and outdoor units. For instance, indoor units may be of the following types: wall-mounted, ceiling, 4-way cassette, ducted or low silhouette ducted. The range of outdoor units available includes single split 1-phase or 3-phase units.
Remote controller display | Cause |
---|---|
Nothing is displayed. | The remote controller is not connected correctly (power trouble). The indoor unit power was cut off after automatic address setting was completed. |
E01 | The remote controller is not connected correctly (remote controller receiving trouble). The remote controller of an indoor unit where the indoor unit address is not set is inadvertently operated. (Communications with the outdoor unit are not possible.) |
E02 | The remote controller is not connected correctly (trouble with sending of the signal from the remote controller to the indoor unit). |
E09 | The indoor unit ceiling panel connector is not connected correctly. |
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 |
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. |
E14 | Main Unit duplication in Simultaneous-operation Multi Control (detected outdoor unit) |
E15 | Automatic Address Alarm (The total capacity of indoor units is too low.) |
E16 | Automatic Address Alarm (The total capacity of indoor units is too high or the total number of indoor units is too many.) |
E18 | Faulty Communication in Group Control Wiring |
E20 | Connection Problem of Indoor/Outdoor Units. |
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 |
H31 | HIC Trouble |
L04 | Outdoor Unit Address Duplication |
L10 | Outdoor Unit Capacity not Set or Invalid |
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), DCCT failure |
P31 | Group Control Error |
Panasonic U-26PE1U6 air conditioner error codes
Panasonic U-26PE1U6 range of air conditioners is comprised of several types of indoor and outdoor units. Each type has its own code (K2, U2, T2 etc.). In spite of all the differences models from the U-26PE1U6 lineup have, they use the same system of error codes. If something goes wrong with an air conditioner, check the code the appliance is displaying to fix it without someone’s help.
Remote controller alarm display | Alarm | Judgment condition | Judgment and correction |
---|---|---|---|
P03 | Abnormal discharge temperature • Discharge temp, detected at or above the specified value. | Stops when temp, exceeds 232 *F. | 1. Check refrigerant cycle (gas leak). 2. Electronic control valve trouble 3. Check tubing sensor (TD). |
P04 | High pressure switch is activated. Compressor motor thermal protector is activated. | Stops when pressure exceeds 600 psi. Stops when temp, exceeds 230 "F. | 1. Check the high pressure switch connector is securely connected. 2. Check the ourdoor unit heat exchanger is not dogged (cooling operation). 3. Check the indoor unit air filter has not become clogged (heating operation). |
P05 | Missing phase detected. (CT disconnected or AC power trouble) | Current value sent from MDC on outdoor unit control PCB is low. No AC power input for 3 minutes or longer: pre-trip - 5 | 1. Check R/S/T power. 2. Check inverter control PCB. 3. Check outdoor unit control PCB. |
P15 | Insufficient gas level detected. | The following conditions continue for 1 minute. • Discharge temp, is 203 *F or higher. • Electronic control valve is at step 480. • Current value from MDC is 2.0 A or less. | Check refrigerant cycle (gas leak). |
P19 | 4-way valve locked • Judgment occurs after compressor has been ON for 5 minutes. | Indoor heat exchanger temp, drops although compressors are ON in heating mode: [min(E1. E2)]£50'F. Indoor heat exchanger temp, rises although compressors are ON in cooling mode: E2 i 104 'F. | 1. Check 4-way valve. 2. Check 4-way valve wiring. 3. Check outdoor unit control PCB. |
P20 | High-pressure protection trouble | If MAX (C1.C2) is 142°F or higher, the compressor stops one. The compressor restarts three time, and if the temperature does not decrease to less than 142°F. the alert “P20" is displayed. | 1. Refrigerant cycle overload operation 2. Outdoor coil temperature sensor C1 or C2 |
P22 | Outdoor unit fan motor trouble • Inverter protection circuit was activated, or lock was detected, at outdoor unit fan motor. | Inverter stops after alarm is detected. | 1. Position detection trouble 2. Overcurrent protection circuit at outdoor unit fan motor was activated. • Check outdoor unit control PCB. • Refer to outdoor unit fan judgment methods. |
P26 | Inverter protection circuit was activated, or G-Tr short-circuit (short time: 0.8 s or less) in inverter control | Inverter stops after alarm is detected. Alarm is output when inverter stops (pre-tnp) consecutively 4 times. | 1. Stops immediately when restarted. • Layer short in the compressor 2. Check inverter control PCB. • Wiring trouble |
Remote controller alarm display | Alarm contents | Judgment condition | Judgment and correction |
P29 | Current detection circuit trouble • AC current value is high even when compressor is stopped. | Inverter stops after alarm is detected. Alarm is output when inverter stops (pre-trip) consecutively 4 times. | 1. Stops immediately when restarted. • Layer short in the compressor 2. Check inverter control PCB. • Wiring trouble |
Compressor motor output trouble. Inverter compressor trouble. MDC trouble | Inverter stops after alarm is detected. | 1. Refrigerant cycle trouble, overload operation 2. Loose screws and contact failure between HIC control PCB and radiating plate 3. Cooling failure of radiating plate 4. Check outdoor unit PCB wiring. |
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Compressor does not run. (Overcurrent protection circuit activates after a certain period of time following compressor start.) | Inverter stops after alarm is detected. | 1. Compressor trouble (locked, etc.) • Replace the compressor. 2. Compressor wiring trouble (missing phase) |
|
Compressor breakdown • Starts to operate but operating frequency drops and compressor stops. | Inverter stops after alarm is detected. | 1. Check power voltage: AC 203 V ± 20 V or 230 V ± 23 V. 2. Refrigerant cycle overload operation 3. Check AC current detection circuit. |
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Inverter control PCB position detection circuit trouble | Inverter stops after alarm is detected. | Position detection circuit is activated even when the compressor 3P connector is disconnected and the compressor operated. • Replace the inverter control PCB. |
|
F04 | Disconnection, open circuit, or short circuit in discharge temp, sensor (TD) | 26. 36 MODEL: Sensor detection trouble (194°F or higher when 15 minutes have elapsed after compressor stopped). (Open circuit) 42 MODEL: Sensor defection trouble (194°F or higher when 60 minutes have elapsed after compressor stopped). (Open circuit) | 1. Check discharge temp, sensor (TD). 2. Check outdoor unit control PCB. |
F06 | Disconnection, open circuit, or short circuit in outdoor heat exchanger temp, sensor (C1) | Open circuit or short circuit | 1. Check outdoor heat exchanger temp, sensor (C1). 2. Check outdoor unit control PCB. |
F07 | Disconnection, open circuit, or short circuit in outdoor heat exchanger temp, sensor (C2) | Open circuit or short circuit | 1. Check outdoor heat exchanger temp, sensor (C2). 2. Check outdoor unit control PCB. |
F08 | Disconnection, open circuit, or short circuit in outdoor air temp, sensor (TO) | Open circuit or short circuit | 1. Check outdoor air temp, sensor (TO). 2. Check outdoor unit control PCB. |
F12 | Disconnection, open circuit, or short circuit in intake temp, sensor (TS) | Open circuit or short circuit | 1. Check intake temp, sensor (TS). 2. Check outdoor unit control PCB. |
Remote controller alarm display | Alarm contents | Judgment condition | Judgment and correction |
F31 | EEPROM trouble | Reading/writing failure | 1. Check EEPROM (IC007). 2. Check outdoor unit control PCB. |
L02 | Mismatch of indoor and outdoor unit types (Espacio. Multi) | Indoor unit judges that type does not match outdoor unit type. | 1. Check indoor unit EEPROM. 2. Check indoor unit control PCB. |
L04 | Settings failure | Duplicated outdoor unit address (system address) | 1. Check outdoor unit system address. 2. Check inter-unit control wiring. |
L07 | Settings failure | Group control wiring is connected to an independent-control indoor | 1. Check inter-unit control wiring. 2. Check indoor unit EEPROM. |
L10 | Settings failure | Outdoor unit capacity not set. | Check outdoor unit EEPROM. |
L13 | Indoor-outdoor unit types | Outdoor unit judges that type does not match indoor unit type. | 1. Check indoor unit EEPROM. 2. Check outdoor unit control PCB. |
E06 | Outdoor unit detected abnormal signal from indoor unit. | Senai signal receiving failure (including failure to verify No. of units) | 1. Check inter-unit control wiring. 2. Check outdoor unit |
E07 | Outdoor unit sending failure to indoor unit | Serial signal sending failure | 1. Check inter-unit control wiring. 2. Check outdoor unit control PCB. |
E14 | Settings failure | Duplicated master unit in simultaneous-operation multi control. (Detected by outdoor unit) | 1. Check inter-unit control wiring. 2. Check indoor unit combination. |
E15 | Automatic address setting failure | Indoor unit capacity too low. | 1. Check inter-unit control wiring. 2. Check outdoor unit control PCB. |
E16 | Automatic address setting failure | Indoor unit capacity too high. | 1. Check inter-unit control wiring. 2. Check outdoor unit control PCB. |
E20 | Automatic address setting failure | Outdoor unit cannot receive any serial signals from indoor units. | 1. Check inter-unit control wiring. 2. Check outdoor unit control PCB. |
E31 | Communications trouble within unit | No communication possible with MDC for 3 minutes or longer. | Check outdoor unit control PCB. |
H01 | Over current | Inverter stops after alarm is detected. | 1. Refrigerant cycle trouble, overload operation 2. Loose screws between HIC control PCB and radiating plate 3. Cooling failure of radiating plate 4. Check outdoor unit PCB wiring. |
Panasonic WH-MDC05F3E5 air conditioner error codes
Panasonic WH-MDC05F3E5 air conditioner is a mono bloc model. More specifically, it is a mono bloc air-to-water heatpump system. In addition to compact design, it boasts such features as energy efficiency (due to inverter technology and a special pump), environment-friendliness (due to non-ozone depletion substances refrigerant), and an easy-to-use control panel.
Diagnosis display | Abnormality/Protection control | Primary location to verify |
---|---|---|
H00 | No abnormality detected | — |
H12 | Indoor/Outdoor capacity unmatched | • Indoor/outdoor connection wire • Indoor/outdoor PCB • Specification and combination table in cataloque |
H15 | Outdoor compressor temperature sensor abnormality | • Compressor temperature sensor (defective or disconnected) |
H20 | Water pump abnormality | • Indoor PCB |
• Water pump (malfunction) | ||
H23 | Indoor refrigerant liquid temperature sensor abnormality | • Refrigerant liquid temperature sensor (defective or disconnected) |
H27 | Service valve error | • 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 | • Water flow switch |
H64 | Refrigerant high pressure abnormality | • Outdoor high pressure sensor (defective or disconnected) |
H65 | Deice circulation error | • Water flow switch sensor (defective or disconnected) • Water pump malfunction • Buffer tank (is used) |
H70 | Back-up heater OLP abnormality | • Back-up heater OLP (Disconnection or activated) |
H72 | Tank sensor abnormal | • Tank sensor |
H76 | Indoor - control panel communication abnormality | • Indoor - control panel (defective or disconnected) |
H90 | Indoor/outdoor abnormal communication | • Internal/external cable connections • Indoor/Outdoor PCB |
H91 | Tank heater OLP abnormality | • 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 | • Pressure switch |
F14 | Outdoor compressor abnormal revolution | • Outdoor compressor |
F15 | Outdoor fan motor lock abnormality | • Outdoor PCB • Outdoor fan motor |
F16 | Total running current protection | • Excess refrigerant • Outdoor PCB |
F20 | Outdoor compressor overheating protection | • Compressor tank temperature sensor • Clogged expansion valve or strainer • Insufficient refrigerant • Outdoor PCB • Compressor |
F22 | I PM (power transistor) overheating protection | • Improper heat exchange • I PM (Power transistor) |
F23 | Outdoor Direct Current (DC) peak detection | • Outdoor PCB • Compressor |
F24 | Refrigeration cycle abnormality | • Insufficient refrigerant • Outdoor PCB • Compressor low compression |
F25 | Coding/Heating cycle changeover abnormality | • 4-way valve • V-coil |
F27 | Pressure switch abnormality | • Pressure switch |
F30 | Water outlet sensor 2 abnormality | • Water outlet sensor 2 (defective or disconnected) |
Diagnosis display | Abnormality/Protection control | Primary location to verify |
F36 | Outdoor air temperature sensor abnormality | • Outdoor air temperature sensor (defective or disconnected) |
F37 | Indoor water inlet temperature sensor abnormality | • Water inlet temperature sensor (defective or disconnected) |
F40 | Outdoor discharge pipe temperature sensor abnormality | • Outdoor discharge pipe temperature sensor (defective or disconnected) |
F41 | PFC control | • Voltage at PFC |
F42 | Outdoor heat exchanger temperature sensor abnormality | • Outdoor heat exchanger temperature sensor (defective or disconnected) |
F43 | Outdoor defrost sensor abnormality | • Outdoor defrost sensor (defective or disconnected) |
F45 | Indoor water outlet temperature sensor abnormality | • 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 | • Outdoor EVA outlet temperature sensor (defective or disconnected) |
F49 | Outdoor bypass outlet temperature sensor abnormality | • 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 |