error codes

High pressure switch in outdoor unit (F12)

Preconditions for fault message:

A pressure of 45 bar or higher has been detected by the high pressure switch for an outdoor unit operating in heating or cooling mode.

Causes:

1. Dust deposits on the heat exchanger of the outdoor unit

2. Air side short circuit in outdoor unit

3. Faulty circulating pump

4. Insufficient water flow in the system

5. Improper seal in the system

6. Service valve closed

7. Expansion valve or filter blocked

8. Too much refrigerant in the system

9. Faulty high pressure sensor and switch on outdoor unit

10. Faulty circuit board on outdoor unit

Fault detection:

Occurs 4x within 20 minutes

Further information can be found in this PDF.

Compressor rotation fault (F14)

Preconditions for fault message:

The position detection circuit in the compressor has recorded an incorrect speed.

Causes:

1. Compressor not connected

2. Faulty outdoor unit circuit board (main board)

3. Faulty compressor

Fault detection:

Occurs 4x within 20 minutes Further information can be found in this PDF.

Further information can be found in this PDF.

DC fan motor on outdoor unit blocked (F15)

Preconditions for fault message:

The speed detected by the hall generator on the fan motor was not between 50 and 2550 min^-1.

Causes:

1. Shut-off following a short circuit in the fan motor coil.

2. Shut-off due to a broken fan motor coil.

3. Shut-off due to a broken wire to the fan motor.

4. Shut-off due to faulty hall generators in fan motor.

5. Disruption due to faulty board in outdoor unit.

Fault detection:

Occurs 2x within 30 minutes.

Further information can be found in this PDF.

Excessive power draw (F16)

Preconditions for fault message:

The transformer (CT) has detected excessive power draw (27.9 A) by the outdoor unit board in cooling or heating mode.

Causes:

1. Too much refrigerant in the system

2. Faulty outdoor unit board (main board)

Fault detection:

Occurs 3x within 20 minutes.

Further information can be found in this PDF.

Compressor overheat protection (F20)

Preconditions for fault message:

The compressor temperature sensor has detected that the compressor casing is above 112 °C in cooling or heating mode.

Causes:

1. Faulty compressor temperature sensor

2. Service valve closed

3. Insufficient refrigerant (leak)

4. Expansion valve or filter blocked

5. Faulty outdoor unit circuit board (main board)

6. Faulty compressor

Fault detection:

Occurs 4x within 30 minutes

Further information can be found in this PDF.

Power transistor module overheat protection (F22)

Preconditions for fault message:

The temperature sensor for the transistor module of the outdoor unit has detected a temperature above 112 °C in cooling or heating mode.

Causes:

1. Faulty fan motor on the outdoor unit

2. Faulty outdoor unit board (main board)

Fault detection:

Occurs 3x within 30 minutes.

Further information can be found in this PDF.

Excess current output (F23)

Preconditions for fault message:

An output current above 40.1 A ±5.0 A (UD07 to 09CE) or 44.7 A ±5.0 A (UD12 to 16CE) in cooling or heating mode has been measured on the main board of the outdoor unit.

Causes:

1. Faulty outdoor unit circuit board (main board)

2. Faulty compressor

Fault detection:

The fault persists for at least 7 seconds.

Further information can be found in this PDF.

Problem in refrigeration circuit (F24)

Preconditions for fault message:

1. In cooling and heating modes, the compressor frequency is higher than the rated frequency.

2. In cooling and heating modes, the operating current is between 0.65 and 1.65 A.

3. In cooling and heating modes, the difference between the water inlet temperature and the fluid temperature of the indoor unit<5 K.

4. In cooling and heating modes, the difference between the water inlet temperature and the fluid temperature of the indoor unit<5 K.

Causes:

1. Faulty water inlet temperature sensor or fluid temperature sensor in the indoor unit

2. Service valve closed

3. Insufficient refrigerant (leak)

4. Expansion valve or filter blocked

5. Faulty outdoor unit circuit board (main board)

6. Poor compressor performance

Fault detection:

Occurs 2x within 20 minutes.

Further information can be found in this PDF.

Problem with switch valve (F25)

Preconditions for fault message:

1. In heating mode, the pipe temperature in the indoor unit is below 0 °C with thermostats active.

2. In cooling mode, the pipe temperature in the indoor unit is above 45 °C thermostats active.

Causes:

1. Sensor error

2. Faulty connection

3. Faulty outdoor unit circuit board (power board or main board)

4. Faulty switch valve

Fault detection:

Occurs 4x within 30 minutes.

Further information can be found in this PDF.

High pressure fault in outdoor unit (F27)

Preconditions for fault message:

The high pressure switch in the outdoor unit remains open when the compressor is shut off.

Causes:

1. Faulty connection

2. Faulty switch

3. Faulty board in outdoor unit (main board)

Fault detection:

The fault persists for at least 1 minute.

Further information can be found in this PDF.

Fault with water outlet temperature sensor 2 in indoor device (F30)

Preconditions for fault message:

When starting and during cooling or heating operation, the measured temperature values from the water outlet temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in indoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Fault with external temperature sensor (F36)

Preconditions for fault message:

When starting and during cooling or heating operation, the measured temperature valves from the external temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in outdoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Fault with water inlet temperature sensor in indoor unit (F37)

Preconditions for fault alert:

When starting and during cooling or heating operation, the measured temperature values from the water inlet temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in indoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Fault with hot gas temperature sensor in outdoor unit (F40)

Preconditions for fault message:

When starting and during cooling or heating operation, the measured temperature valves from the hot gas temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in outdoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Inverter controller fault (PFC, F41)

Preconditions for fault message:

In cooling and heating modes, the PFC breaker measures an unusually high DC voltage on the main board of the outdoor unit.

Causes:

1. Excess power supply voltage

2. Unequal resistances in the compressor coils

3. Faulty circuit board on outdoor unit

Fault detection:

Occurs 4x within 10 minutes

Further information can be found in this PDF.

Fault with heat exchanger temperature sensor in outdoor unit (F42)

Preconditions for fault message:

When starting and during cooling or heating operation, the measured temperature values from the heat exchanger temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in outdoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Fault with defrosting temperature sensor in outdoor unit (F43)

Preconditions for fault message:

When starting and during cooling or heating operation, the measured temperature values from the defrosting temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in outdoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Fault with water outlet temperature sensor in indoor device (F45)

Prerequisites for fault alert:

When starting and during cooling or heating operation, the measured temperature values from the water outlet temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in indoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Transformer in outdoor unit is open (F46)

Preconditions for fault message:

A transformer (CT) has been determined to be defective if the operating frequency of the compressor (≥ rated frequency) and the transformer’s measured power draw (less than 0.65 A) do not match for a period of 20 seconds.

Causes:

1. Transformer is faulty

2. Faulty outdoor unit circuit board (main board)

3. Faulty compressor

Fault detection:

Occurs 3x within 20 minutes

Further information can be found in this PDF.

Fault with evaporator outlet temperature sensor in outdoor unit (F48)

Preconditions for fault message:

When starting and during cooling or heating operation, the measured temperature values from the evaporator outlet temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in outdoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Fault with bypass outlet temperature sensor in outdoor unit (F49)

Preconditions for fault message:

When starting and during cooling or heating operation, the measured temperature values from the bypass outlet temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in outdoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

High pressure protection during cooling in outdoor unit (F95)

Preconditions for fault message:

A pressure of 40 bar or higher has been detected by the high pressure sensor in the outdoor unit.

Causes:

1. Dust deposits on the heat exchanger of the outdoor unit

2. Air side short circuit in outdoor unit

3. Two-way service valve closed

4. Faulty fan motor on the outdoor unit

5. Expansion valve or filter blocked

6. Too much refrigerant in the system

7. Faulty high pressure sensor in outdoor unit

8. Faulty board in outdoor unit (main board)

Further information can be found in this PDF.

Unsuitable unit performance (H12)

Preconditions for the fault message:

When starting the cooling and heating operation, the outdoor unit checks the performance combination of indoor and outdoor unit for reliability.

Causes:

1. Incorrect models connected to each other

2. Incorrect indoor and/or outdoor unit circuit boards (main boards) used

3. Faulty circuit board in indoor/outdoor unit circuit boards

Fault detection:

Incorrect measurement for at least 90 seconds.

Further information can be found in this PDF.

Fault with compressor temperature sensor (H15)

Preconditions for fault message:

When starting and during cooling or heating operation, the measured temperature values from the compressor temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in outdoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Fault with fluid temperature sensor in indoor unit (H23)

Preconditions for fault message:

When starting and during cooling or heating operation, the measured temperature values from the fluid temperature sensor in the indoor unit are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in indoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Sun sensor malfunction (H28):

Preconditions for the fault message:

Error code continues for more than 5 seconds.

Causes:

1. Faulty connection

2. Solar sensor defective

3. Faulty inner sub-board

CAUTION:

For safety reasons and to avoid component failure, always switch off the power supply before removing and connecting the component

Detection of the fault:

1. Check connection at CN207.
2. Measure the resistance of the sensor matching characteristic
3. Change the inner sub-board

Swimming pool sensor malfunction (H28):

Preconditions for the fault message:

Error code continues for more than 5 seconds.

Causes:

1. Faulty connection

2. Pool sensor defective

3. Faulty inner sub-board

CAUTION:

For safety reasons and to avoid component failure, always switch off the power supply before removing and connecting the component

Detection of the fault:

1. Check connection at CN204.
2. Measure the resistance of the sensor matching characteristic
3. Change the inner sub-board

Buffer tank sensor malfunction (H28):

Preconditions for the fault message:

Error code continues for more than 5 seconds.

Causes:

1. Faulty connector

2. Buffer tank sensor defective

3. Faulty inner sub-board

CAUTION:

For safety reasons and to avoid component failure, always switch off the power supply before removing and connecting the component

Detection of the fault:

1. Check connection at CN205.
2. Remove sensor from sub-board Measure resistance of sensor and compare with characteristic
3. Change the inner sub-board

Low pressure compressor protection (H42)

Preconditions for fault message:

In heating mode and after the compressor has been operating for 5 minutes, the pipe temperature sensor in the outdoor unit measures a temperature below -29 °C or above 26 °C.

Causes:

1. Dust deposits on the heat exchanger of the outdoor unit

2. Air side short circuit in outdoor unit

3. Two-way service valve partially closed

4. Faulty fan motor on the outdoor unit

5. Insufficient refrigerant (leak)

6. Expansion valve or filter blocked

7. Defective pipe temperature sensor in outdoor unit

8. Faulty board in outdoor unit (main board)

Further information can be found in this PDF.

 Zone 1 sensor malfunction (H43):

Preconditions for the fault message:

Error code continues for more than 5 seconds.

Causes:

1. Faulty connection

2. Buffer tank sensor defective

3. Faulty inner sub-board

CAUTION:

For safety reasons and to avoid component failure, always switch off the power supply before you remove and connect the component

Detection of the fault:

1. Check the connection of the connector to switch off

2. Check the connector of the sub-circuit board of zone 1 - the circuit board the resistance of the sensor characteristic curve of zone 1

3. Change circuit board

Zone 2 sensor malfunction (H44):

Preconditions for the fault message:

Error code continues for more than 5 seconds.

Causes:

1.Faulty connection

2. Remove from sub-board, check sensor properties. Test measurement resistance

CAUTION:

For safety reasons and to avoid component failure, always switch off the power supply before removing and connecting the component Detection of the fault:

Switch off the power

1. supply test plug connection.

2. Disconnect from the sub-board, check sensor properties. Test measurement resistance

3. Change circuit board

Fault on the water-side flow monitor (H62)

Preconditions for the fault message:

During cooling and heating operation, the water flow is monitored by the flow monitor in the indoor unit in order to detect an interruption in the flow.

Causes:

1. Faulty circulating pump

2. Improper seal in the system

3. Faulty connection

4. Faulty flow monitor

5. Faulty circuit board in indoor unit (main board)

Fault detection:

The fault persists for 10 seconds (no monitoring for 9 minutes after compressor start-up or restart)

Further information can be found in this PDF.

Defective low pressure sensor in outdoor unit (H63)

Preconditions for fault message:

When in heating mode, the output signal from the low pressure sensor in the outdoor units gives a value of 0 or 5 V DC.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty circuit board on outdoor unit

Fault detection:

Occurs 4x within 20 minutes

Further information can be found in this PDF.

Defective high pressure sensor in outdoor unit (H64)

Preconditions for fault message:

When in heating or cooling mode, the output signal from the high pressure sensor in the outdoor units gives a value of 0 or 5 V DC.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty circuit board on outdoor unit

Fault detection:

Occurs 4x within 20 minutes

Further information can be found in this PDF.

Incorrect water circulation in defrost mode 2 (H65)

Preconditions for the fault message:

During the defrost process (defrost mode 2) and during the defrost, water flow through the heat exchanger was determined.

Cause:

1. Unwanted water flow through the heat exchanger of the heat pump, possibly caused by an external circulation pump

2. Defective flow switch

3. Defective circulating pump in the indoor unit

4. Defective motherboard

Detection of the fault:

Water malfunction continues> 10 seconds.

Fault overload protection of the indoor unit electric heating element (H70)

Preconditions for fault message:

While the indoor unit electric heating element is switched on, there is no voltage on the indoor unit electric heating element or the overload protection is open.

Causes:

1. Incorrect connection of the power supply

2. Faulty connection

3. Faulty overload protection of the indoor unit electric heating element.

4. Faulty circuit board in outdoor unit (main board)

Fault detection:

The fault persists for at least 60 seconds.

Further information can be found in this PDF.

Fault in the hot water tank temperature sensor (H72)

Preconditions for fault message:

If the parameter for the tank connection is set to YES, the temperature values measured by the hot water tank temperature sensor are checked for plausibility.

Causes:

1. Faulty connection

2. Sensor error

3. Faulty board in indoor unit (main board)

Fault detection:

Incorrect measurement value for at least 5 seconds.

Further information can be found in this PDF.

Fault in data transmission with the control panel of the indoor unit (H76)

Preconditions for fault message:

In standby, in cooling and in heating mode if there is a fault in the indoor unit control panel

Causes:

1. Faulty connections

2. Faulty control panel

3. Faulty circuit board in outdoor unit (main board)

Further information can be found in this PDF.

Faulty communication between indoor and outdoor units (H90)

Preconditions for fault message

In cooling or heating mode, it is checked whether signals received from the outdoor unit are correct during data transmission.

Causes:

1. Faulty outdoor unit circuit board (main board)

2. Faulty indoor unit circuit board (main board)

3. Faulty connection between indoor and outdoor units

4. Damaged cabling between indoor and outdoor units

5. Incorrect data transmission due to incorrect waveform of the power supply

Detection of the fault:

The fault is present after 1 minute of operation

For more information, see this PDF.

Fault overload protection of the indoor unit electric heating element (H91)

Preconditions for fault message:

While the hot water electric heating element is switched on, there is no voltage across the hot water electric heating element or the overload protection is open.

Causes:

1. Faulty connection

2. Faulty hot water electric heating element overload protection.

3. Faulty circuit board in indoor unit (main board)

Fault detection:

The fault persists for at least 60 seconds.

Further information can be found in this PDF.

Power supply indoor/outdoor unit faulty (H95)

Preconditions for fault message:

The power supply is monitored by the indoor/outdoor unit communication

Causes:

1. Insufficient power supply

2. Faulty board in outdoor unit (power supply or main board)

Further information can be found in this PDF.

High pressure fault in heating mode (H98)

Preconditions for fault message:

in heating mode, a pressure of 40 bar or higher has been detected by the high pressure sensor in the outdoor unit.

Causes:

1. Faulty circulating pump

2. Insufficient water flow in the system

3. Improper seal in the system

4. Service valve closed

5. Expansion valve or filter blocked

6. Too much refrigerant in the system

7. Faulty high pressure sensor in outdoor unit

8. Faulty board in outdoor unit (main board)

Further information can be found in this PDF.

Frost protection in the indoor unit

Preconditions for the fault message:

During the frost protection control in cooling mode, the refrigerant temperature in the indoor unit drops below 0°C

Cause:

1. Faulty circulating pump

2. Insufficient water flow in the system

3. Improper seal in the system

4. Two-way service valve partially closed

5. Expansion valve or filter blocked

6. Insufficient refrigerant (leak)

7. Faulty fluid temperature sensor

8. Faulty circuit board in outdoor unit (main board)

Further information can be found in this PDF.