23 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 |
|---|---|---|
| 41-416-02 | Reno HE37C | 2005–present |
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Your boiler's computer has encountered an internal error and has stopped working to prevent any further issues.
Your boiler is struggling to accurately measure the temperature of the water flowing through your heating system, so it has stopped working as a safety precaution.
Your boiler has detected an internal computer error that prevents it from starting safely.
Your boiler has failed to light after several attempts and has locked itself out to prevent a build-up of unburnt gas.
Your boiler's internal computer is struggling to read data from its sensors, which prevents it from safely controlling the heat.
Your boiler's computer is having trouble communicating internally, which is preventing it from starting up safely.
Your boiler is repeatedly failing to keep its flame lit, which means it has safely shut down to prevent gas from escaping unburned.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside it, likely due to a faulty electrical sensor.
Your boiler has lost the ability to read the temperature of the water flowing through your heating system, so it has safely shut itself down.
Your boiler has detected a faulty electrical signal regarding the water temperature, meaning it has temporarily stopped heating your taps to prevent any damage.
Your boiler has lost the signal from the sensor that monitors your hot water temperature, which will likely stop your hot water from working correctly.
Your boiler is not receiving the correct amount of electricity from your home's power supply, which is preventing it from starting up correctly.
Your boiler has stopped working because the amount of water inside your heating system has dropped below the minimum level required to operate safely.
Your boiler is having a communication error with an external thermostat control, preventing it from heating your home properly.
Your boiler has detected that the water pressure inside the heating system is too high or that the sensor measuring this pressure is not working correctly.
Your boiler is struggling to talk to its control panel to confirm it has enough water inside, causing it to shut down for safety.
Your boiler is struggling to accurately measure the temperature of the water returning to it from your radiators, so it has stopped working to prevent potential overheating.
Your boiler has detected a faulty connection to the sensor that monitors the temperature of the exhaust fumes, causing it to shut down for safety reasons.
Your boiler has lost communication with a sensor that monitors the temperature of the exhaust gases, causing it to shut down for safety reasons.
Your boiler has lost the ability to 'see' how much water is inside, so it has shut down to protect itself from potentially running dry.
Your boiler's main control panel has lost its connection to the internal computer, meaning it can no longer send or receive instructions.
Your boiler has shut down because it is producing more heat than your radiators or pipes can safely carry away at once.
Your boiler's air circulation system has stopped working, which means the device cannot safely ignite or produce heat.
BoilerFaultCodes