34 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Baxi Duo-tec Combi
This boiler uses LED flash patterns
Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →
The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.
| GC number | Appliance (register name) | Produced |
|---|---|---|
| 47-075-13 | Combi Instant 80 e | 2003–2005 |
| 47-075-06 | Combi 80 e | 2001–2011 |
Tap any card for details
Your boiler has detected a problem with its internal temperature sensors, which means it cannot accurately tell how hot the water is and has stopped working for safety.
Your boiler has detected a system error that it cannot clear itself, which could be anything from a temporary glitch to an internal electronic part failure.
Your boiler is trying to start but cannot light the gas flame, meaning you will not have any heating or hot water.
Your boiler has detected that the fan is spinning but not reaching the required speed to safely clear waste gases, preventing the burner from lighting.
Your boiler has detected that water is not circulating properly through the system even though the pump is trying to run.
Your boiler is failing to clear its system of air before starting, so it has safely shut down to prevent ignition.
Your boiler is failing to light the fuel inside even though it is trying to start, so it has safely shut itself down to prevent a gas build-up.
Your boiler's internal computer has crashed or is struggling to process the reset command, preventing it from starting up again safely.
Your boiler is lighting up but shutting off shortly after because it cannot confirm that the flame is staying on, meaning you currently have no heating or hot water.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler is failing to light the gas to create a flame, which means your heating and hot water will not work.
Your boiler is struggling to light or keep its flame burning, which has caused it to shut down for safety.
Your boiler has sensed that it is becoming too hot and has automatically shut down for safety purposes.
Your boiler has detected that water is not circulating correctly through the system, which prevents it from heating up safely.
Your boiler has detected an issue with the air flow or the internal fan, which means it cannot safely exhaust fumes and has stopped working as a precaution.
Your boiler is struggling to detect the temperature of the water coming from your taps, which means it cannot reliably provide hot water.
Your boiler has stopped working because it cannot correctly detect the temperature of the water being used for your radiators.
Your boiler is struggling to breathe because it cannot clear out exhaust gases properly, so it has safely shut itself down to prevent fumes from building up inside your home.
Your boiler has detected that it is overheating and has automatically switched itself off to prevent damage.
Your boiler has detected an issue with the system that pushes air through the unit and expels gases safely outside, so it has shut down to prevent unsafe operation.
Your boiler is struggling to move water around your heating system because there is either not enough pressure inside the pipes or the internal pump has stopped working.
Your boiler is struggling to detect the temperature of the water, which means it cannot reliably provide hot water for your taps or shower.
Your boiler's temperature sensor is providing incorrect readings, which prevents the unit from heating your home or water reliably.
Your boiler is struggling to accurately measure the temperature of the water coming out of your taps, which may cause your hot water to fluctuate or stop working entirely.
Your boiler is struggling to monitor the temperature of the water used for your radiators, causing the system to stop running as a safety precaution.
Your boiler is not firing up because it isn't receiving the necessary signal or fuel to start the heating process.
Your boiler thinks a hot water tap is turned on even when it isn't, which is preventing the system from working correctly.
Your boiler has detected an issue with the internal fan that clears waste gases, meaning the system has safely shut down to prevent any hazards.
Your boiler has tried to ignite but was unable to stay lit, meaning your heating and hot water will not work until it is reset or repaired.
Your boiler is trying to start but the flame is not catching, meaning you currently have no heating or hot water.
Your boiler has become dangerously pressurized, which is causing it to automatically release water to prevent a potential rupture.
Your boiler has attempted to light the gas burner multiple times but has failed to detect a flame, causing it to shut down for safety reasons.
Your boiler has detected an internal error and has entered a lock-out state, meaning it has switched itself off to prevent damage.
Your boiler has detected that it got too hot and has automatically switched itself off to stay safe.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes