17 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Baxi 800
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Your boiler has lost communication with the sensor that monitors the temperature outside your home, preventing it from adjusting its heat output efficiently.
Your boiler's temperature sensor has failed or is disconnected, meaning the system cannot accurately measure how hot the water is for your heating.
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 lost the ability to accurately measure the temperature of your hot water, so it has shut down to prevent overheating.
Your boiler has become too hot and has shut itself down as a safety precaution to prevent damage.
Your boiler has switched itself off because the water pressure in the system has dropped too low to operate safely.
Your boiler has detected that hot water isn't moving through the system properly, which is causing it to shut down to prevent overheating.
Your boiler has detected that hot combustion gases are escaping or overheating near the flue, so it has shut itself down as a safety precaution.
Your boiler has shut down because it detected that the exhaust gases have become too hot, which is a safety feature to prevent damage to the internal components.
Your boiler is failing to light the gas flame, which means you currently have no heating or hot water.
Your boiler has detected a problem with the fan that clears away waste gases, causing the system to shut down for safety.
Your boiler has detected a problem with the fan that clears away waste gases, causing the system to shut down for safety.
Your boiler is struggling to accurately detect the water pressure in the system, which is preventing it from heating up.
Your boiler's computer control board has developed a communication fault and is unable to manage the system correctly.
Your boiler's internal computer has encountered a memory or electrical glitch and has temporarily locked itself down to prevent safety issues.
Your boiler has detected that water is not moving through the system correctly, which causes it to shut down to prevent overheating.
Your boiler is struggling to detect the movement of water inside the system, causing it to continuously restart its internal pump instead of heating your home.
BoilerFaultCodes