26 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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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 |
|---|---|---|
| 47-116-45 | Combi A 30 MFFI Combi A | 2005–2007 |
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Your boiler has detected that it has become too hot and has automatically shut itself down to prevent damage.
Your boiler has detected a problem with the fan that safely removes exhaust gases, meaning it has shut down as a safety precaution.
Your boiler has failed to ignite the flame reliably and has stopped trying for your safety.
Your boiler is failing to create a spark to ignite the gas, meaning it cannot provide heating or hot water.
Your boiler is struggling to switch between providing hot water and heating your home due to a jammed internal mechanical part.
Your boiler has stopped working because the water is not being pumped around the system properly.
Your boiler is failing to detect the flame needed to heat your water, so it has shut down for safety.
Your boiler has detected an electrical safety issue or a component failure that prevents it from starting up safely.
Your boiler is struggling to confirm that the burner has lit correctly, causing it to shut down for safety.
Your boiler has failed to detect a flame and has locked out to ensure your safety.
Your boiler's electronic control system has detected an internal electrical failure that prevents it from starting up safely.
Your boiler has detected that water is not flowing through the system correctly, likely due to a blockage in the internal filter.
Your boiler has switched itself off because it has reached an unsafe temperature and needs to cool down before it can be used again.
Your boiler is not receiving a signal from your thermostat, which means your heating won't turn on even if you try to increase the temperature.
Your boiler's internal mechanism that controls the flame size has failed, meaning the system cannot regulate its heat output properly and has shut down for safety.
Your boiler has detected a problem with the sensor that monitors the temperature of the water being sent to your radiators, which prevents it from heating your home safely.
Your boiler has detected that the water pressure inside the system is too low for it to operate safely.
Your boiler is having trouble switching between heating your radiators and providing hot water because an internal switch is stuck or failing.
Your boiler's built-in timer or clock has encountered a communication error, meaning the heating may not turn on at your scheduled times.
Your boiler has switched itself off completely to prevent damage because a safety sensor has detected a problem with how it is operating.
Your boiler has stopped working because the water pressure inside the heating system has dropped too low.
Your boiler is unable to light the gas flame to provide heating or hot water, and has shut down as a safety precaution.
Your boiler has detected that the water pressure is too low to operate safely and has shut down to prevent damage.
Your boiler has detected that water is not moving through the system properly, which is preventing it from heating up safely.
Your boiler has got too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler has failed its internal safety check and has shut itself down to prevent a fault from becoming more serious.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes