19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has lost its electrical connection to the gas supply unit, meaning it cannot ignite to provide heating or hot water.
Your boiler has detected an internal issue with the gas control system and has shut down as a safety precaution.
Your boiler has detected a fault with the internal sensor that monitors the temperature of your central heating water, causing the system to stop working as a safety precaution.
Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing the system to shut down for safety.
Your boiler has detected a problem with the sensor that monitors the temperature of the water returning from your radiators.
Your boiler's internal computer parts are having trouble talking to each other, which means the system has stopped working for safety.
Your boiler is struggling to move water around the system before it starts the heating process, which is often caused by a blockage or a pump issue.
Your boiler has switched itself off because it has reached an unsafe temperature, usually due to a lack of water flow or a circulation problem.
Your boiler has stopped working because the water pressure in the system has dropped too low and needs topping up.
Your boiler is struggling to move hot water around the system, which is usually caused by a blockage or a pump issue that is preventing the unit from cooling itself down.
Your boiler has lost its flame while running, which means it has safely shut down to prevent issues.
Your boiler has shut down because a sensor has detected that the exhaust gases are becoming too hot, which is a safety feature to prevent damage.
Your boiler has failed to light because it is not receiving enough gas or cannot detect the flame used to heat your water.
Your boiler has lost its gas supply, meaning it cannot light the flame to provide heating or hot water.
Your boiler has noticed that water is not circulating correctly or the temperature sensors are giving conflicting readings.
Your boiler has stopped working because the internal fan, which safely exhausts gases, is not spinning at the correct speed or has lost power.
Your boiler has detected that water is not moving through the system correctly, causing it to overheat quickly.
Your boiler has detected a problem with the sensor that monitors the temperature of your hot water, meaning your taps may not get as hot as they should or stay consistent.
Your boiler thinks a flame is present even when it should be off, causing it to shut down for safety.
BoilerFaultCodes