Baxi Duo-tec 2 Combi GA Boilers

28 fault codes documented

09

Error 09 - Gas Valve Connection Cable Fault

This error code indicates an issue with the gas valve connection cable. The boiler's display will show the spanner symbol and the numeric error code, suggesting an internal component problem.

109

Error 109 - Pre-circulation Fault

This error code indicates a problem with the pre-circulation phase of the boiler's operation. The boiler's display will show the spanner symbol and the numeric error code, suggesting an issue with water flow.

110

Error 110 - Safety Thermostat Activated

This error code indicates that a safety thermostat has operated, likely due to the boiler overheating. The boiler's display will show the spanner symbol and the numeric error code, signifying a safety shutdown.

117

Error E117 - Primary System Water Pressure Too High

The boiler has detected that the primary system water pressure has exceeded 3 bar, which has caused the safety pressure valve to activate. This prevents damage to the heating system.

118

Error E118 - Primary System Water Pressure Too Low

The central heating system pressure is too low, indicated by the gauge reading below 1 bar or the E118 error code on the display. The boiler will not operate correctly until the pressure is restored.

125

Error 125 - Primary Circulation Fault

This error code indicates a problem with the primary circulation of water within the boiler or heating system. The boiler's display will show the spanner symbol and the numeric error code.

128

Error 128 - Flame Failure

This error code indicates that the boiler's flame has failed to ignite or has extinguished during operation. The boiler's display will show the spanner symbol and the numeric error code, preventing normal heating.

130

Error 130 - Flue NTC sensor Operated

This error code indicates that the flue NTC sensor has been activated, likely due to high flue gas temperatures. The boiler's display will show the spanner symbol and the numeric error code, signifying a safety shutdown.

133

Error 133 - Gas Supply Interruption or Flame Failure

This error code signifies an interruption in the gas supply to the boiler or a failure of the flame to ignite. The boiler's display will show the spanner symbol and the numeric error code.

134

Error 134 - Gas Valve Open Without Gas Detected

This error code indicates that the gas valve is open, but the boiler is not detecting any gas flow or ignition. The boiler's display will show the spanner symbol and the numeric error code, preventing ignition.

135

Error 135 - Internal Gas Supply Interruption

This error code indicates an internal interruption in the boiler's gas supply system. The boiler's display will show the spanner symbol and the numeric error code, signifying an internal fault.

15

Error 15 - Gas Valve Fault

This error code signifies a fault within the gas valve component of the boiler. The boiler's display will show the spanner symbol and the numeric error code, indicating an internal issue.

154

Error 154 - Flow/Return sensor Temperature Test Failed

This error code indicates a failure in the boiler's self-test for the flow and return temperature sensors. The boiler's display will show the spanner symbol and the numeric error code, suggesting a sensor or water flow issue.

160

Error 160 - Fan or Fan Wiring Fault

This error code indicates a problem with the boiler's fan or its associated wiring. The boiler's display will show the spanner symbol and the numeric error code, preventing safe operation.

20

Error 20 - Central Heating NTC sensor Fault

This error code indicates a problem with the Central Heating NTC (Negative Temperature Coefficient) sensor. The boiler's display will show the spanner symbol and the numeric error code, suggesting a sensor malfunction.

270

Error 270 - Circulation Fault (Dry Fire)

This error code indicates a serious circulation fault, often referred to as 'dry fire', where the boiler attempts to fire without adequate water circulation. The display will show the spanner symbol and the numeric error code.

28

Error 28 - Flue NTC sensor Fault

This error code indicates a problem with the Flue NTC (Negative Temperature Coefficient) sensor. The boiler's display will show the spanner symbol and the numeric error code, suggesting a sensor malfunction.

321

Error 321 - Hot Water NTC sensor Fault

This error code indicates a problem with the Hot Water NTC (Negative Temperature Coefficient) sensor, which monitors the domestic hot water temperature. The boiler's display will show the spanner symbol and the numeric error code.

384

Error 384 - False Flame Detected

This error code indicates that the boiler's flame detection system is detecting a flame when none should be present, or at an inappropriate time. The boiler's display will show the spanner symbol and the numeric error code.

40

Error 40 - Central Heating Return NTC sensor Fault

This error code indicates a problem with the Central Heating Return NTC (Negative Temperature Coefficient) sensor. The boiler's display will show the spanner symbol and the numeric error code, suggesting a sensor malfunction.

55

Error 55 - Calibration Required

This error code indicates that the boiler requires a calibration process. The boiler's display will show the spanner symbol and the numeric error code, signifying that system adjustments are needed.

E symbol

Error symbol 'E' illuminated - Boiler fault preventing burner start

The 'E' (Error) symbol is illuminated or flashing on the boiler display, indicating a general fault that is preventing the burner from starting. This is often accompanied by a specific numeric error code.

No Gas Supply

Boiler not working - No gas supply to property

The boiler is not operating and other gas appliances in the property (e.g., cooker or gas fire) are also not working, indicating a potential interruption to the gas supply.

No Power / Display Off

Boiler display off - No electrical power to boiler

The boiler display is unlit, and the boiler is not working, suggesting a complete lack of electrical supply. This prevents the boiler from operating and any error codes from being shown.

Room Thermostat Too Low

Boiler not heating - Room thermostat set too low

The boiler is not producing heat because the room thermostat (if fitted) is set to a temperature lower than the current room temperature, so it is not calling for heat. The boiler is correctly waiting for a heat demand.

Sd

'Sd' message - Service Due Reminder

The boiler display shows 'Sd' alternating with the boiler temperature, indicating that an annual service is due. This message appears after approximately 11 months of operation.

Spanner Symbol

Spanner symbol illuminated - Non-resettable boiler fault

The spanner symbol is illuminated or flashing on the boiler display, indicating a fault that typically cannot be reset by the user and requires professional attention. Specific error codes will usually be displayed alongside this symbol.

Timer Not Calling for Heat

Boiler not heating - Timer not set for central heating

The boiler is not producing heat because the external timer (if fitted) is not set to 'ON' or configured to call for central heating at the current time. The boiler will wait for a demand signal.