28 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 |
|---|---|---|
| 41-116-30 | Clas HE R 12 | 2008–2013 |
Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.
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Your boiler has detected that it is getting too hot and has automatically shut down to prevent damage to its internal systems.
Your boiler has detected that there is not enough water flowing through the system to keep it running safely.
Your boiler has stopped working because the water isn't flowing properly through the system.
Your boiler has stopped working because water is not moving through the system quickly enough to prevent it from getting too hot.
Your boiler has failed to ignite the burner properly and has locked out for safety.
Your boiler has shut down because the water pressure inside the system is too low to operate safely.
Your boiler has temporarily stopped working because it cannot properly read the temperature of the water flowing through it due to a faulty sensor connection.
Your boiler has temporarily stopped working because it cannot properly read the temperature of the water returning from your radiators.
Your boiler is having trouble communicating with the outdoor weather sensor, which helps it decide how hard to work based on the outside temperature.
Your boiler has detected a fault with the sensor that measures the temperature of the water being sent to your radiators, which means it cannot heat your home safely.
Your boiler has failed to ignite properly and stopped working because it did not detect a flame after several attempts.
Your boiler is struggling to move water through the system properly, which is causing it to stop running to prevent overheating.
Your boiler is failing to ignite properly and has stopped working to keep you safe.
Your boiler's internal computer memory has encountered a reading or writing error, preventing the system from functioning correctly.
Your boiler's internal computer is struggling to talk to its control parts, preventing it from functioning correctly.
Your boiler’s main internal control board has developed a technical fault, preventing the system from starting up or operating safely.
Your boiler has been manually reset more than five times in fifteen minutes and has temporarily locked itself for safety.
Your boiler's internal computer is experiencing a communication error, meaning it has lost track of its own operational state and cannot safely run.
The internal computer that controls your boiler is experiencing a communication error and cannot operate the system safely.
Your boiler's internal computer is experiencing a communication error and has shut down to prevent potential hardware damage.
Your boiler is failing to light the gas even though it is trying to start up.
Your boiler’s internal safety sensor thinks the burner is still lit even though it should be turned off, which prevents the system from starting safely.
Your boiler is struggling to keep the flame stable, which is preventing it from heating your water or home properly.
Your boiler tried to start up but couldn't create a flame on its first attempt, meaning you likely have no heating or hot water right now.
Your boiler has tried to start twice but has failed to successfully light its internal flame.
Your boiler has stopped during operation because the main burner flame has unexpectedly gone out.
Your boiler's fan, which is essential for safely venting exhaust gases, is struggling to reach the speed it needs to operate, causing the system to stop as a safety precaution.
Your boiler has detected a break in a safety circuit designed to shut the system down if it overheats, which has caused it to stop working completely.
BoilerFaultCodes