30 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 |
|---|---|---|
| 47-416-11 | QuanTec HR28C | 2012–present |
| 47-416-14 | Quantec HR28CP | 2015–present |
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Your boiler's computer is unable to process internal signals correctly, causing it to shut down for safety.
Your boiler has stopped producing hot water because it has detected a fault with the sensor that measures the temperature of the water going to your taps.
Your boiler has failed to start up after multiple attempts and has now locked itself out for safety reasons.
Your boiler has tried to start five times but failed to ignite, so it has safely shut itself down to prevent a build-up of unburnt gas.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent any damage or safety issues.
Your boiler's computer has experienced a critical memory error, preventing it from starting up safely.
Your boiler has detected an issue with the sensor that monitors the temperature of the gases leaving your flue, meaning it has shut down as a precaution to ensure safe operation.
Your boiler has attempted to restart itself too many times in a short period and has now locked itself out for safety reasons.
Your boiler has detected multiple errors in a short period and has locked itself out for safety reasons to prevent a repeating fault.
Your boiler has lost the correct water pressure needed to circulate heat around your home.
Your boiler has detected that the water pressure inside your heating system has dropped too low to operate safely.
Your boiler has detected a flame inside when the system is supposed to be turned off, which is a safety mechanism triggered to prevent incorrect operation.
Your boiler has stopped working because it cannot safely clear waste gases, so it has shut down to prevent unsafe operation.
Your boiler has stopped working because it cannot safely detect that the flame is lit, so it has shut down to prevent gas from building up.
Your boiler has lost the ability to accurately measure the temperature of the water flowing through it, so it has shut down to prevent damage.
Your boiler has detected an issue with the sensor that monitors the safety of the exhaust gases and has turned itself off to stay safe.
Your boiler has lost the ability to measure the temperature of the hot water being produced, so it has safely shut down to prevent overheating.
Your boiler is trying to start but cannot light the internal flame, so it has shut down as a safety precaution to prevent gas from building up.
Your boiler has detected that the electricity coming from your home's wall socket is unstable and outside the safe voltage range it needs to operate correctly.
Your boiler has stopped working because the amount of water inside your heating system has dropped below the necessary level to operate safely.
Your boiler is working fine for your radiators, but a specific internal component is failing to switch over to provide hot water to your taps.
Your boiler has lost all power, meaning it cannot currently provide any heating or hot water to your home.
Your boiler is struggling to read the outside temperature and is likely using a backup setting to keep your home warm.
Your boiler has shut itself down because it is getting too hot inside, usually because water is not flowing through your heating system properly.
Your boiler has detected an error and needs a manual restart to clear the internal safety lockout.
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has shut down to prevent potential overheating.
Your boiler has stopped working because it cannot correctly detect the temperature of the water being heated, so it has shut down as a safety precaution.
Your boiler has detected that a component responsible for controlling the gas supply is not responding correctly, so it has safely shut down to prevent any risk.
Your boiler is struggling to detect the amount of water in the system, which is preventing it from heating your home or water safely.
Your boiler has taken in too much water, causing internal pressure to rise above safe operational limits.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes