11 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Promax System High Efficiency
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Your boiler has lost its connection to the sensor that monitors the temperature of the water in your heating system, causing the boiler to stop working.
Your boiler has detected a problem with the sensor that monitors the temperature of the exhaust gases, causing it to stop running for safety.
Your boiler's temperature sensor for hot water has developed a fault, meaning the system may struggle to heat your water to the correct temperature.
Your boiler has shut down because it has detected an unsafe increase in temperature and has triggered a safety cut-out to prevent damage.
Your boiler has detected that the water pressure is too low for it to run safely and has shut down as a precaution.
Your boiler has stopped working because water is not moving through the system correctly, which could be due to a blockage or a pump issue.
Your boiler has sensed that the exhaust gases are getting too hot and has shut down as a safety precaution to prevent damage.
Your boiler has failed to light because it either cannot get enough gas or cannot detect a flame once ignited.
Your boiler has stopped working because the internal fan, which safely clears exhaust gases, isn't spinning at the correct speed.
Your boiler has sensed that water is not circulating properly before it starts the heating process, which is usually caused by an air lock or a blockage.
Your boiler is currently running in a special service mode used by engineers to test its performance, and it is not actually reporting a fault.
BoilerFaultCodes