Fujitsu Waterstage SuperHP Heat Pumps

The user interface displays '10: Outdoor sensor', indicating an issue with the outdoor temperature sensor (Location: BX4 (X84)). This error typically triggers an automatic reset.

The user interface displays '100: 2 master clocks on bus', indicating that there are two devices configured as master clocks on the same communication bus, causing a conflict. This error typically triggers an automatic reset.

The user interface displays '102: Clock without running supply', indicating that the internal clock is not receiving continuous power, which can lead to timekeeping errors. This error typically triggers an automatic reset.

The user interface displays '105: Maintenance message'. This indicates a general maintenance alert, often a reminder for scheduled service or a non-critical operational issue. This error typically triggers an automatic reset.

The user interface displays '121: HC1 flow temperature too low', indicating that the flow temperature for Heating Circuit 1 is below the set threshold. This suggests insufficient heat delivery. This error typically triggers an automatic reset.

The user interface displays '122: HC2 flow temperature too low', indicating that the flow temperature for Heating Circuit 2 is below the set threshold. This suggests insufficient heat delivery. This error typically triggers an automatic reset.

The user interface displays '126: DHW charge monitoring', indicating an issue with monitoring the domestic hot water charging process. This means the system cannot properly track or control DHW heating. This error typically triggers an automatic reset.

The user interface displays '127: Anti-legionella temperature', indicating that the system failed to reach or maintain the required temperature for anti-legionella protection in the DHW tank. This error typically triggers an automatic reset.

The user interface displays '134: Heat pump alarm summary', also shown as E20. This is a general alarm indicating one or more underlying issues within the heat pump system. A manual reset is required.

The user interface displays '138: No heat pump control sensor', indicating that a critical sensor required for proper heat pump control is missing or not detected. This error typically triggers an automatic reset.

The user interface displays '30: Flow sensor 1', indicating an issue with flow sensor 1 (Location: BX1 (X80)) in the hydraulic system. This error typically triggers an automatic reset.

The user interface displays '31: Cooling flow sensor 1', indicating an issue with the flow sensor specifically for the cooling circuit (Location: BX1 (X80)). This error typically triggers an automatic reset.

The user interface displays '32: Flow sensor 2', indicating an issue with flow sensor 2 (Location: BX31 (X153)), often in a secondary or different hydraulic circuit. This error typically triggers an automatic reset.

The user interface displays '33: Heat pump flow temperature sensor error', indicating an issue with the sensor measuring the outgoing flow temperature of the heat pump (Location: BX1 (X80)). This error typically triggers an automatic reset.

The user interface displays '44: Heat pump return temperature sensor error', indicating an issue with the sensor measuring the return water temperature to the heat pump (Location: BX2 (X80)). This error typically triggers an automatic reset.

The user interface displays '50: DHW temperature sensor 1', indicating an issue with the domestic hot water temperature sensor (Location: BX3 (X84)). This error typically triggers an automatic reset.

The user interface displays '60: Room sensor 1', indicating an issue with the primary room temperature sensor. This error typically triggers an automatic reset.

The user interface displays '65: Room sensor 2', indicating an issue with the secondary room temperature sensor. This error typically triggers an automatic reset.

The user interface displays '76: Special sensor 1', indicating an issue with a specialized sensor (Location: BX). This error typically triggers an automatic reset.

The user interface displays '83: BSB wire short-circuit', indicating a short circuit in the BSB communication wiring, which can disrupt system communication. This error typically triggers an automatic reset.

The user interface displays '84: BSB, address collision', indicating that two devices on the BSB bus (Building System Bus) have been assigned the same address, causing a communication conflict. This error typically triggers an automatic reset.

The user interface displays '85: Radio communication error', indicating a problem with wireless communication between system components. This error typically triggers an automatic reset.

The user interface displays '98: Extension module 1', indicating an issue with extension module 1, an add-on component to the heat pump system. This error typically triggers an automatic reset.

The user interface displays '99: Extension module 2', indicating an issue with extension module 2, an add-on component to the heat pump system. This error typically triggers an automatic reset.

The indoor unit's interface LED flashes continuously (1 second on, 1 second off) when the system is performing a pump-down operation. This is a normal function, not an error state.

The indoor unit's interface LED2 (Green) remaining constantly lit while LED1 (Red) is off indicates the system is currently in defrosting mode. This is a normal operational status, not an error.

The circulation pump's green LED is flashing, indicating that the system is in venting mode, which typically runs for 10 minutes to remove air from the hydraulic circuit. This is a normal operational status.

The Green LED for the circulation pump is off, indicating that the pump is not receiving power or is not operating. This prevents water circulation.

This indicator signifies a communication problem between the indoor and outdoor heat pump units. It also corresponds to the outdoor unit displaying '1 Flash' for a serial forward transfer error after pressing the ENTER switch on the outdoor unit's electronic board.

This indicates that the discharge temperature has exceeded safe limits, triggering a protective shutdown. The outdoor unit may also show '11 Flashes' for discharge temperature protection (permanent stoppage) after pressing the ENTER switch.

This indicates that the compressor's internal temperature has exceeded safe limits, triggering a protective shutdown. The outdoor unit may also show '12 Flashes' for compressor temperature protection (permanent stoppage) after pressing the ENTER switch.

This indicates an abnormal pressure condition detected within the outdoor unit, which could be due to issues with the refrigerant system.

This indicates that the refrigerant pressure in the system has dropped to an abnormally low level. The outdoor unit may also show '20 Flashes' for low pressure abnormal after pressing the ENTER switch.

This indicates that the system is drawing too much electrical current, triggering an overload protection mechanism.

This error indicates an issue with how the units are connected, suggesting an improper series configuration or an incompatible device connection.

This indicates an irregular or insufficient power supply to the indoor hydraulic unit. This could be due to unstable voltage or a connection issue.

This error suggests a problem with the serial communication between the main controller board and the interface board within the indoor unit itself.

This indicates an issue with the heat pump's capacity signal, which could be an open circuit (no signal) or a short circuit (incorrect signal).

This error indicates a malfunction with the thermistor (temperature sensor) located in the hydraulic indoor unit's heat exchanger.

This error indicates an irregular or insufficient power supply to the outdoor heat pump unit. This could be due to unstable voltage or a connection issue.

This signifies a fault with the main Printed Circuit Board (PCB) in the outdoor heat pump unit, which controls its core functions.

This error indicates a problem with the inverter system in the outdoor unit, which controls the compressor speed. The outdoor unit may also show '18 Flashes' after pressing the ENTER switch.

This indicates a problem with the active filter circuit, which helps manage power quality and harmonics in the system.

This signifies an error with the Intelligent Power Module (IPM) in the outdoor unit, a critical component for power management and control.

This error indicates that the outdoor unit experienced a brief power interruption, triggering a protective shutdown to prevent damage.

This indicates a fault with a magnetic relay in the outdoor unit, often involved in switching power to various components.

This indicates a problem with the discharge thermistor, a temperature sensor crucial for monitoring the compressor's discharge temperature. The outdoor unit may also show '2 Flashes' for this error after pressing the ENTER switch.

This indicates a problem with the compressor thermistor, which monitors the compressor's internal temperature. The outdoor unit may also show '8 Flashes' for this error after pressing the ENTER switch.

This indicates a problem with the heat exchanger thermistor, which measures the temperature at the outlet or an intermediate point of the heat exchanger. The outdoor unit may also show '4 Flashes' for a heat-exchange thermistor (outlet) error after pressing the ENTER switch.

This indicates a problem with the outdoor temperature thermistor, which measures the ambient air temperature. The outdoor unit may also show '7 Flashes' for an outdoor temperature thermistor error after pressing the ENTER switch.

This indicates a problem with the thermistor measuring the temperature of the heat sink in the outdoor unit. The outdoor unit may also show '9 Flashes' for a heat sink thermistor error after pressing the ENTER switch.

This indicates a problem with the thermistor associated with the expansion valve in the outdoor unit. The outdoor unit may also show '6 Flashes' for an expansion valve thermistor error after pressing the ENTER switch.

This error indicates a malfunction with the current sensor, which monitors electrical current within the heat pump system. This could lead to incorrect power readings or protective shutdowns.

This indicates a problem with a pressure sensor or switch in the system. The outdoor unit may also show '3 Flashes' for a general pressure sensor error, or more specifically '23 Flashes' for Discharge pressure sensor error and '24 Flashes' for Suction pressure sensor error after pressing the ENTER switch.

This error indicates that an overcurrent protection mechanism has been activated, causing the unit to trip due to excessive electrical current. The outdoor unit may also show '13 Flashes' for a current trip (permanent stoppage) after pressing the ENTER switch.

This indicates a problem with the compressor's starting sequence or its internal position detection. The outdoor unit may also show '14 Flashes' for compressor position error or '15 Flashes' for compressor start up error after pressing the ENTER switch.

This indicates a problem with the fan motor 1 in the outdoor unit. The outdoor unit may also show '16 Flashes' for a fan motor (1) error (permanent stoppage) after pressing the ENTER switch.

This indicates a problem with the fan motor 2 in the outdoor unit (if equipped with two fans). The outdoor unit may also show '17 Flashes' for a fan motor (2) error (permanent stoppage) after pressing the ENTER switch.

The red LED on the circulation pump is flashing, indicating an operating error that requires attention and is not self-restarting.

Both the red and green LEDs on the circulation pump are flashing, indicating an operating error that the system is attempting to resolve with an automatic restart.