33 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 |
|---|---|---|
| 47-157-23 | CaprizPlus 24a | 2012–present |
| 47-157-19 | CaprizPlus 24 | 2011–present |
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Your boiler's control panel has developed a communication problem or a mechanical failure and cannot send your instructions to the main system.
Your boiler has stopped working because it cannot correctly measure the temperature of the water used to heat your home.
Your boiler has sensed a problem with the internal sensor that monitors the temperature of the water returning from your radiators, causing the system to shut down for safety.
Your boiler has stopped working because it cannot accurately measure the temperature of the water used for your heating.
Your boiler has stopped working because it cannot correctly measure the temperature of the water returning from your radiators.
Your boiler has detected that it is getting too hot and has shut down as a safety precaution.
Your boiler has stopped working because the water pressure inside the system has dropped too low.
Your boiler has shut down because the water is heating up too quickly or isn't circulating properly through the system.
Your boiler has detected that water isn't moving through the system properly, causing it to shut down to prevent overheating.
Your boiler has stopped working because the internal component that controls the gas flow has failed or lost electrical connection.
Your boiler has shut down because it cannot detect the flame used to heat your water, even though it may have ignited.
Your boiler has tried to light several times but cannot establish a steady flame, which means your heating and hot water will not work.
Your boiler started to heat up but the flame went out unexpectedly while it was running.
Your boiler has detected an issue with the way waste gases are being pushed out of the system, causing it to shut down for safety.
Your boiler has lost the stable electrical communication it needs to talk to its internal parts or external controls, preventing it from starting up correctly.
Your boiler is unable to safely control the flow of gas required to ignite the flame, so it has shut down to prevent a safety hazard.
Your boiler has detected a safety issue where the gas valve is not closing properly, leading to a lockout for your protection.
Your boiler's internal computer has suffered a memory failure and can no longer process the instructions needed to run safely.
Your boiler's computer is experiencing an internal electronic failure and cannot safely control your heating or hot water system.
Your boiler's internal computer has become too hot and has shut down the system to prevent any damage to the electronics.
Your boiler's electronic control board part is struggling to recognise the flame, causing the system to shut down for safety.
Your boiler is struggling to maintain a steady flame, causing the system to stop working frequently for safety reasons.
Your boiler's internal control panel and main computer board are failing to communicate with each other because they don't recognise each other's software version.
Your boiler has stopped working because it cannot correctly measure the temperature of the water leaving the unit.
Your boiler has noticed that its two temperature sensors are giving conflicting readings, causing it to shut down for safety.
Your boiler's internal sensor is unable to correctly read the water pressure, which has caused the system to stop working as a safety precaution.
Your boiler has lost track of the water pressure because the internal sensor is either broken or sending an incorrect signal.
Your boiler's safety device has detected the main heat exchanger is getting too hot and has shut the system down to prevent permanent damage.
Your boiler is unable to control the flow of gas into the burner, which means it will stop working to keep you safe.
Your boiler has detected that the internal pump, which moves water around your heating system, is not communicating properly with the control board.
Your boiler has stopped working because it thinks the temperature sensors are measuring the wrong heat levels or have been wired incorrectly.
Your boiler has detected that its internal temperature sensors are improperly positioned or sending conflicting signals, which prevents the system from heating up safely.
Your boiler has detected a problem with the safety connection for your underfloor heating system, which usually means a sensor is loose or has shut the system down to prevent floor damage.
Not faults — these are normal operating states. Tap to expand.
BoilerFaultCodes