28 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Ideal Classic SE
This boiler uses LED flash patterns
Count the flashes in one repeating group before the pause. That number is your fault code. Do not reset until you have noted it. How to read fault codes →
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Your boiler has detected an electrical fault with the sensor that monitors your hot water temperature, meaning it cannot heat water safely.
Your boiler has detected a communication issue or a component failure within its central heating temperature sensing system, meaning it cannot accurately monitor the water temperature for your radiators.
Your boiler's hot water sensor is struggling to communicate with the main control board, meaning the system cannot accurately monitor the water temperature.
Your boiler is failing to keep its small pilot flame burning, which means it cannot fire up to provide heating or hot water.
Your boiler's small starter flame is lit, but the main burner is failing to ignite because it isn't receiving the gas flow it needs to heat your home.
Your boiler has detected that the electrical wiring coming into the unit is swapped or incorrectly connected, preventing it from starting safely.
Your boiler has detected that the water leaving the unit is getting too hot, causing it to shut down to prevent damage.
Your boiler's main control computer has developed an internal electrical fault and can no longer manage the heating process safely.
Your boiler has detected a signal for a flame when there shouldn't be one, or there is an electrical fault within the ignition system preventing it from starting safely.
Your boiler is not receiving any electrical power, which is why the lights are off and it isn't working.
Your boiler has detected a problem with its internal fan or the power supply to it, preventing the unit from starting safely.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler’s internal computer has encountered a critical failure and can no longer control the heating system safely.
Your boiler is trying to light but the flame is cutting out almost immediately, which is usually caused by a dirty sensor or a problem with the gas supply.
This light is actually a positive signal showing that your boiler's internal electrical fuse is working correctly and the control board has power.
Your boiler is failing to ignite and has locked itself out for safety after several unsuccessful attempts to start.
Your boiler has detected that there is not enough water in the central heating system to operate safely, so it has shut down to protect itself.
Your boiler is failing to ignite the main gas flame, which means your heating and hot water will not work.
Your boiler has no power, which means it cannot turn on to provide heating or hot water.
Your boiler is correctly receiving power from your home's electrical supply and is in its normal standby mode.
Your boiler is currently trying to light the gas burner with a spark, but it is failing to sense a flame and stay on.
This light simply shows that your boiler is trying to light itself, which is a normal part of its startup sequence.
Your boiler has detected that the internal fan or air pressure system is sticking in the 'on' position, preventing the ignition sequence from starting safely.
Your boiler has detected an issue with the fan that safely removes exhaust gases, meaning it cannot start up for safety reasons.
Your boiler has lost power to its main control board, meaning it cannot operate and you will not have any heating or hot water.
Your boiler is failing to light the gas flame, meaning your heating and hot water will not work.
Your boiler has become too hot and has automatically switched itself off to prevent any damage.
Your boiler is failing to ignite the small starter flame, which means the main burner cannot catch light to provide heating or hot water.
BoilerFaultCodes