17 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has registered a flue gas safety thermostat trip, meaning the safety device has detected an issue with the exhaust gases leaving the flue.
Your boiler has stopped working because moisture or condensation is not draining away properly, which triggers a safety lock-out.
Your boiler has detected a safety-related issue with its internal sensors or temperature controls, causing it to lock out for safety.
Your boiler has detected an issue with the internal components controlling the flow of water between your heating and hot water systems.
Your boiler has locked out because the electronic control board received an unexpected data sequence or signal from its internal components.
Your boiler has detected an internal electrical or wiring connection issue that is preventing it from operating safely.
Your boiler has detected a temperature problem related to the domestic hot water or heating sensor, causing it to lock out for safety.
Your boiler has detected an issue with the air pressure or airflow sensor, which stops the boiler from safely igniting.
Your Biasi boiler has detected an internal electronic or electrical detection fault, causing it to lock out for safety.
Your boiler has detected an issue with the gas valve modulation, which means it cannot safely or accurately control the gas supply to heat your home.
Your boiler has detected an issue with the heating system's return water sensor or temperature monitoring, causing it to temporarily stop operating to protect itself.
Your boiler has detected an issue with the domestic hot water heat exchanger, which may prevent your hot water from working properly.
Your boiler has detected an issue with the domestic hot water heat exchanger, which usually means it is struggling to heat your water properly or has experienced a temperature problem.
Your boiler has detected an internal electronic or sensor communication error, which causes the system to safely lock out to prevent potential damage.
Your boiler has detected an internal electronic or parameter setting error and has stopped operating to protect itself.
Your boiler has failed to light the gas flame and has locked itself out for safety.
Your boiler has temporarily shut down because the water inside it has become dangerously hot, which usually points to a blockage in the flow.
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BoilerFaultCodes