BoilerFaultCodes.com

Ideal Systemiser SE Fault Codes

Regular Natural Gas 15-24 kW 2005-2012 Discontinued
GC Numbers: 41-397-9041-397-9141-397-9241-397-93

Replaced by: Logic Heat

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Most common fault codes

0
Your boiler thinks a flame is present even when it hasn't been lit yet, which is causing it to shut down for safety.
Gas Safe engineer required · £120-280
1
Your boiler has lost power to its main control system due to an electrical fault, meaning it cannot start the heating or hot water process.
Gas Safe engineer required · £150-350
2
Your boiler is failing to light the gas burner, meaning it cannot create the heat needed for your heating or hot water.
May be DIY safe · £100-£280

All 34 fault codes

Code Severity Plain English
0 High Your boiler thinks a flame is present even when it hasn't been lit yet, which is causing it to shut down for safety.
1 High Your boiler has lost power to its main control system due to an electrical fault, meaning it cannot start the heating or hot water process.
2 High Your boiler is failing to light the gas burner, meaning it cannot create the heat needed for your heating or hot water.
400 High Your boiler's internal computer has encountered an electronic error and is unable to communicate with its controls to provide heat.
401 High Your boiler's internal computer brain has experienced a malfunction and can no longer communicate with the heating system.
403 High Your boiler’s internal computer has encountered a critical electronic error and can no longer communicate with the main system.
404 High Your boiler has experienced a fundamental software or memory error that has caused it to shut down securely for safety.
405 High Your boiler’s internal computer has encountered a critical electronic error and can no longer control the heating system safely.
406 High Your boiler's internal computer brain has developed an electrical fault and is unable to communicate with its own sensors.
407 High Your boiler's internal computer has encountered a critical electronic error and can no longer control the heating system safely.
408 High Your boiler has detected a problem with how air or water is flowing through the system and has shut down as a safety precaution.
410 High Your boiler’s internal computer brain has developed a critical electronic fault and can no longer communicate with the rest of the system.
411 High Your boiler's internal computer has encountered a critical electronic error and can no longer communicate with the rest of the system.
413 High Your boiler’s internal control computer has encountered a critical electrical error and can no longer manage the system safely.
414 High Your boiler's internal computer has encountered a critical electronic error and has stopped working to protect the system.
415 High Your boiler's internal computer has suffered a technical malfunction and can no longer control the heating system safely.
416 High Your boiler has experienced an internal computer error and cannot safely operate the heating or hot water until the main control parts are checked.
417 High Your boiler's computer control board has experienced an internal electrical fault and is unable to communicate with its components.
424 High Your boiler has detected that the internal temperature sensors have been wired or installed in the wrong positions, preventing it from heating safely.
426 High Your boiler is not receiving enough gas to stay lit safely, which is preventing your heating and hot water from working.
430 High Your boiler has detected that water is moving too slowly or not at all through the system, causing a heat imbalance that has triggered a safety shutdown.
431 High Your boiler has detected a fault with its temperature sensor, which means the system cannot safely monitor the heat of the water and has stopped working as a precaution.
432 High Your boiler has detected a fault with one of its internal temperature sensors, which is preventing the system from heating up safely.
436 High Your boiler has stopped working because one of its internal temperature sensors has broken or become disconnected.
437 High Your boiler has stopped working because a sensor that monitors water temperature has lost its connection or stopped sending information.
441 High Your boiler's internal computer brain has developed a terminal electronic glitch and can no longer control the heating process safely.
442 High Your boiler has experienced a nervous breakdown in its main computer brain, which means it cannot communicate with itself and has stopped working for safety.
460 High Your boiler's internal computer has encountered a critical error and can no longer communicate with the rest of the system.
528 High Your boiler's fan is failing to start or communicate with the control board, meaning the system cannot safely clear exhaust fumes to stay running.
529 High Your boiler's fan is spinning but the control board cannot detect its speed, preventing the boiler from firing up for safety.
912 High Your boiler has shut down because it believes the internal water pressure is too low or it is getting too hot inside.
918 High Your boiler has shut down because the water inside it has become too hot, which is often caused by a blockage or a pump that isn't moving water through the system correctly.
919 High Your boiler has switched itself off because the water returning to the unit is too hot, meaning the heat isn't being distributed around your home properly.
925 High Your boiler is heating up too quickly and has shut down to prevent overheating, likely because the water isn't moving through the system properly.

Ideal Systemiser SE is discontinued — time for a new one?

Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.

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