33 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Mexico HE
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Your boiler is unable to ignite the small pilot flame required to start the main heating process.
Your boiler is failing to keep its small pilot flame burning, which prevents the main heating unit from starting up.
Your boiler has started part of the ignition process and has a pilot light, but the main burner is failing to ignite to provide heat.
Your boiler is unable to start the small flame needed to ignite the main burner, meaning your heating and hot water will not work.
Your boiler's pilot light is going out as soon as you let go of the ignition button, preventing the main burner from starting up.
Your boiler has successfully lit the small pilot flame, but the main burner is failing to ignite to provide heat or hot water.
Your boiler has managed to light the small pilot flame, but the main gas burners are failing to ignite to heat your home.
Your boiler is likely having trouble reading the temperature setting because the control knob is faulty or incorrectly positioned.
Your boiler's viewing window is likely damaged or leaking, which means you cannot safely monitor the pilot light or burner flame.
Your boiler is unable to light the small starter flame needed to fire up the main heating system.
Your boiler's control system has detected a specific internal communication failure or electrical fault related to the main burner ignition sequence.
Your boiler is failing to light because the spark system responsible for igniting the gas is not working correctly.
Your boiler has detected a communication failure with the component that controls the gas flow to the burner, meaning the boiler cannot fire up to provide heat.
Your boiler's main burner is not receiving the correct flow of gas needed to ignite and stay lit, meaning your heating system will not work.
Your boiler has switched itself off because it got too hot, and it needs to cool down before it can be restarted.
Your boiler's main burner is failing to ignite or communicate correctly, meaning your heating and hot water will likely stop working.
Your boiler's right-hand burner is failing to ignite, meaning the system cannot generate any heat for your radiators or water.
Your boiler is failing to light the burner because the electrical cable responsible for creating the igniting spark is faulty or disconnected.
Your boiler is unable to light because the component that delivers gas to the burner is blocked or failing.
Your boiler is unable to light the small starter flame required to ignite the main heating system.
Your boiler is failing to ignite because it cannot detect or receive a steady supply of gas to create a flame.
Your boiler has detected an issue with the internal flue vent that prevents it from clearing exhaust gases safely, causing it to shut down to protect your home.
Your boiler has stopped working because it has detected an internal temperature sensor fault or is overheating.
Your boiler's main burner component is failing to ignite or stay lit, meaning your heating system cannot generate warmth.
Your boiler is unable to light the burner because a critical ignition cable is damaged or disconnected.
There is a possible smell or leakage of gas which could lead to fire or explosion if not addressed immediately.
Your boiler has stopped working because it failed to light or stay lit, triggering a safety shutdown.
Your boiler is currently running its internal fan, which is a standard part of the startup or cooling process.
Your boiler is receiving power and is currently in standby mode, which is the normal state when everything is functioning correctly.
Your heating system is losing water, which means there is likely a leak or a failing pressure relief valve causing the boiler to stop working correctly.
Your boiler is receiving power from the mains supply and is ready to operate.
This light is showing you that the boiler is currently trying to light the burner and is a normal part of the startup process.
Your boiler has shut down because wind or a blockage is pushing harmful exhaust fumes back down the chimney instead of letting them escape outside.
BoilerFaultCodes