NIBE S2125 Air/Water Heat Pump

This alarm indicates a communication issue with the inverter, typically lasting for 20 seconds, and suggests the inverter may be unpowered, broken, or has a poor connection.

This alarm signifies that the inverter's safety function has reduced the compressor speed below the lowest permitted working range, indicating a potential issue with the compressor or refrigerant circuit.

The CPU LED on the base board (AA2) is continuously lit, indicating that the CPU is not functioning correctly.

The green DEFROST LED on the base board (AA2) is continuously lit, indicating that a defrosting cycle is currently in progress.

The red ERROR LED on the base board (AA2) is continuously lit, indicating an active, continuous alarm that requires attention.

Any of the K1-K5 LEDs on the base board (AA2) are continuously lit, indicating that the corresponding relay has been activated (is on).

The green PWR LED on the base board (AA2) is continuously lit, which is the normal indication that the base board is receiving power.

The green PWR-INV LED is continuously lit, which is the normal indication that the inverter is receiving power.

This alarm indicates that the current to the inverter has been too high 3 times within 2 hours or continuously for 1 hour, possibly due to a defective inverter.

This alarm means the return line is hotter than the flow line, indicating that the supply and return lines, or their sensors, have been incorrectly connected.

This alarm indicates that the compressor has failed to start when required 3 times within 2 hours, potentially due to a defective inverter or compressor.

This alarm indicates that the pressure difference between BP9 and BP8 has been too low at compressor start 3 times within 30 minutes, suggesting a fault in the pressure sensors or compressor.

This alarm indicates that the fan has failed to start 5 times consecutively, likely due to a blockage or a connection issue.

The green CPU LED on the base board (AA2) is flashing, which is the normal indication that the CPU is operating correctly.

The green DEFROST LED on the base board (AA2) is flashing, indicating that some protection function is currently active.

The red ERROR LED on the base board (AA2) is flashing, indicating an active info alarm, which is typically a temporary or less severe alert.

The green EXT COM LED on the base board (AA2) is flashing, which is the normal indication of active communication with the indoor module or control module.

The green INT COM LED on the base board (AA2) is flashing, which is the normal indication of active communication with the inverter.

The room temperature is higher than desired, often due to incorrect settings in the indoor module or control module.

This alarm means the inverter tried to heat up the compressor but failed, possibly due to a fault in the inverter or a loose discharge sensor.

This alarm indicates that the output current from the inverter to the compressor has been temporarily too high 3 times within 2 hours or continuously for 1 hour.

This alarm indicates that the power output from the inverter has been too high 3 times within 2 hours or continuously for 1 hour, possibly due to poor heating medium flow or a defective compressor.

This alarm is triggered by 3 repeated instances of high discharge temperature within 4 hours, typically indicating a disruption or fault in the refrigerant circuit.

Ice accumulation on the fan, grille, or fan cone of the outdoor unit can impede operation and airflow.

This alarm indicates that the Heat Pump has the wrong base board (PCBA) installed, meaning it is not suitable for the S2125 model.

The hot water temperature is too low or no hot water is available, which can be caused by high consumption, incorrect settings, or a clogged filterball.

The room temperature is lower than desired, possibly due to closed thermostats, incorrect settings, or air in the heating system.

This alarm indicates that the defrosting flow is low, usually caused by a clogged particle filter or generally low flow in the system.

This alarm occurs after 5 repeated instances of low evaporation temperature within 4 hours, suggesting a lack of refrigerant or a blockage.

This alarm occurs if the system experiences low low-pressure conditions 5 times within 4 hours, indicating a problem with refrigerant flow or pressure.

This alarm suggests a disruption in supply voltage or a temporary inverter fault that occurs 3 times within 2 hours or continuously for 1 hour.

The CPU LED on the base board (AA2) is not lit, indicating that the CPU (Central Processing Unit) is not receiving power.

The green DEFROST LED on the base board (AA2) is not lit, which is the normal indication when no defrosting or protection functions are currently active.

The red ERROR LED on the base board (AA2) is not lit, which is the normal indication when there are no active alarms or errors.

The green EXT COM LED on the base board (AA2) is not lit, indicating a lack of communication with the indoor module or control module.

The green INT COM LED on the base board (AA2) is not lit, indicating a lack of communication with the inverter.

Any of the K1-K5 LEDs on the base board (AA2) are not lit, indicating that the corresponding relay is in its de-energised (off) position.

The green PWR LED on the base board (AA2) is off, indicating that the base board is not receiving power.

The green PWR-INV LED is not lit, indicating that the inverter is not receiving power.

This alarm signifies that the inverter has reached its maximum working temperature due to poor cooling, occurring 3 times within 2 hours or continuously for 1 hour.

This alarm indicates the inverter has reached its maximum working temperature due to poor cooling, occurring 3 times within 2 hours or continuously for 1 hour, potentially linked to low supply voltage.

This alarm indicates 2 repeated LP/HP/FQ alarms within 2.5 hours, signaling persistent pressure switch or over-temperature issues due to poor heating medium flow.

This alarm indicates that a compressor phase is missing, occurring 3 times within 2 hours or continuously for 1 minute, often due to a disruption in supply voltage or incorrect wiring.

This alarm indicates 5 repeated high pressure alarms within 4 hours, often due to poor heating medium flow, a clogged filter, or disruption in the refrigerant circuit.

This alarm indicates 5 repeated low pressure alarms within 4 hours, suggesting a lack of refrigerant or a blocked expansion valve.

This alarm signals 10 repeated defrostings according to protection conditions, often caused by poor airflow or ice/snow accumulation.

The NIBE S2125 Heat Pump fails to start. This can be due to lack of demand from the indoor module/control module, temperature conditions, minimum time between compressor starts not being met, or an active alarm.

The NIBE S2125 Heat Pump is not communicating with its paired indoor module or control module, which could be due to installation or cable issues.

This alarm signifies that the inverter has experienced a temporary fault 2 times within 60 minutes, potentially due to a disruption in supply voltage.

This alarm indicates that the inverter has experienced a temporary fault 3 times within 2 hours, likely due to a disruption in supply voltage.

This alarm indicates that the discharge sensor (BT14) or high pressure sensor (BP9) has either come loose or is defective, leading to incorrect measurement values.

These alarms indicate an open-circuit or short-circuit fault on various sensor inputs (BT3, BT12, BT14, BT15, BT16, BT17, BT28, BP8, BP9, BT84).

This alarm indicates that the compressor stops less than 5 minutes after starting, often due to poor flow, incorrect settings, or issues within the refrigerant circuit.

This alarm covers several unspecified faults related to the inverter, including incompatibility, missing configuration files, or charge error configuration.

This alarm appears after 10 consecutive failed defrosting attempts, typically due to low system temperature, poor flow, or insufficient available system volume.