18 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler is failing to switch off even when it should, which means it will continue to run constantly and may overheat.
Your boiler is making unusual noises because of internal blockages or issues with how it regulates heat or water flow, which can put unnecessary strain on the system.
Your boiler is struggling to light smoothly and is building up gas before catching, causing a small bang or flash when it starts.
The control knob for your gas supply has become stuck or seized, making it difficult or impossible to safely turn the boiler on or off.
Your boiler is making loud banging or kettling noises because internal mineral deposits have built up, restricting water flow and causing it to overheat.
Your boiler is struggling to correctly regulate the flow of water, which is causing it to stop operating properly.
Your boiler is struggling to detect enough water flowing through it to safely start your hot water.
Your boiler is struggling to breathe properly because it is recycling its own exhaust fumes, which means it cannot burn gas safely.
Your boiler is failing to ignite the flame needed to heat your water or home, which means the system has stopped working entirely.
Your boiler is failing to ignite because it is not receiving a steady supply of gas to create the pilot flame needed to start the system.
Your boiler is failing to stay lit, which means it cannot safely heat your home or provide hot water.
Your boiler is failing to ignite because it cannot receive or properly process the gas needed to create a flame.
Your boiler's pilot light is failing to remain lit, which prevents the main burner from igniting and means you currently have no heating or hot water.
Your boiler's small starter flame is too weak to safely ignite the main burner, causing the system to shut down to prevent gas build-up.
Your boiler is struggling to keep the fire lit safely, which could prevent your heating or hot water from working consistently.
Your boiler is struggling to heat the water to the right temperature because the water is flowing through the system too quickly or the gas supply isn't strong enough.
Your boiler is not burning fuel cleanly, which means it is producing dangerous fumes that could lead to carbon monoxide buildup inside your home.
Your boiler is not burning fuel correctly, which is causing soot to build up and creating a serious risk of carbon monoxide production.
BoilerFaultCodes