17 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has safely shut down because either the pipe that carries away waste gases outside or the pipe that drains acidic wastewater is blocked.
Your boiler has detected a problem with its internal fan and has shut down as a safety precaution, meaning you will not have any heating or hot water.
Your boiler has detected that the flame inside has gone out unexpectedly and it cannot stay alight, so it has safely shut itself down to prevent gas from building up.
Your boiler has detected a flame inside before it actually released any gas, which is a safety lockout to prevent potential hazards.
Your boiler's temperature sensor is providing faulty information, causing it to stop operating to ensure your safety.
Your boiler has detected that your heating pipes have been connected the wrong way around, preventing it from heating your home properly.
Your boiler has detected an issue with the valve that controls the supply of gas inside the appliance, meaning it has safely shut down to prevent any risk.
Your boiler has failed to light the flame, so it has safely shut itself down to prevent a build-up of unburnt gas.
Your boiler is struggling because the electricity supply coming into your home is weaker than the level required to operate the unit safely.
Your boiler has temporarily stopped because it cannot detect enough water moving through the system to keep it cool and safe.
Your boiler is having trouble communicating with the temperature sensor located outside your home, so it is using a default setting to keep your heating running.
Your boiler has temporarily shut down because the internal temperature got too high.
Your boiler's main electronic brain has encountered an internal error and cannot safely continue running.
Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has shut down as a precaution to prevent overheating.
Your boiler is failing to communicate with your wall thermostat, meaning it cannot tell when to turn on or off.
Your boiler's computer module has been replaced but has not been programmed to match your specific heating system, preventing the boiler from functioning.
Your boiler has temporarily locked itself out because it tried to start up too many times without success.
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BoilerFaultCodes