24 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 |
|---|---|---|
| 47-464-01 | EHYKOMB33AA | 2013–present |
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Your system has detected a potential electronic reading error during its routine startup check and has stopped working to prevent further issues.
Your hybrid system has detected that the water temperature inside the unit is getting too hot, so it has temporarily shut down to prevent damage.
The system's control sensors have been incorrectly wired or swapped during installation or maintenance, preventing the boiler from correctly reading temperatures.
Your boiler has temporarily paused its operation due to a technical error and is waiting for conditions to change or a minor internal issue to clear before it can restart itself.
Your boiler is failing to light the gas even though it is trying to start up.
Your boiler is struggling to keep its flame lit, which is usually caused by a blockage in the drainage pipe or an incorrect gas supply.
Your boiler is struggling to detect a flame, which means it cannot fire up to provide heating or hot water.
Your boiler has detected that its internal fan is not spinning at the correct speed, which has caused the system to stop working for safety.
Your heating system is struggling to judge the weather correctly because the outdoor temperature sensor has stopped sending a reliable signal.
Your heating system is currently unable to read the temperature correctly because one of its internal probes has developed a fault or a loose connection.
Your heat pump is struggling to read the temperature correctly because a sensor has stopped sending a signal.
Your heating system is struggling to read the temperature correctly because one of its internal sensors has stopped sending a clear signal.
Your heat pump is unable to read temperature data correctly because a communication link to one of its internal sensors has been lost.
Your boiler is struggling to detect if water is moving correctly through the system, which is preventing it from heating your home or water safely.
Your heating system is struggling to read the temperature correctly because a monitoring probe has developed a fault.
Your heat pump system is experiencing an error because it is unable to accurately read the current temperature of its internal components.
Your hybrid boiler is having trouble reading a temperature measurement from one of its internal sensors, which is causing the system to stop operating correctly.
Your boiler's internal thermometer that measures the temperature of the water coming back from your radiators has developed a fault, meaning the system cannot regulate its heat correctly.
Your boiler has detected an issue with the sensor that monitors exhaust gases, and it has shut down as a safety precaution.
Your boiler has detected an internal electrical fault with the component that controls the gas supply, meaning it cannot safely start up to heat your home.
Your boiler's safety system has detected a potential electronic fault with the mechanism that controls the gas flow, so it has shut down to keep your home safe.
Your boiler has detected that the water pressure in the system is too low for it to operate safely.
Your boiler's temperature sensor for hot water has stopped working correctly, meaning your system cannot accurately monitor or provide hot water.
Your boiler is having trouble reading the temperature of your hot water tank, which means it cannot heat your water correctly.
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BoilerFaultCodes