19 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Greenstar Utility 18/25 (ERP)
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Wind or air is blowing back down your boiler's chimney, which is preventing the exhaust fumes from escaping safely.
Your boiler's internal pump or motor is not receiving power or has stopped working, meaning it cannot circulate heat through your system.
Your boiler's internal computer has encountered an error and is unable to communicate properly with the rest of the system.
Your boiler’s internal flame sensor is dirty and can no longer see the fire, causing the system to shut down for safety.
Your boiler's main control board has detected a setup error, meaning it no longer recognises which specific model it is meant to be.
Your boiler is having trouble creating the spark or flame needed to start up because the internal ignition components are out of alignment.
Your boiler has lost its electrical supply and won't turn on, meaning it cannot provide any heating or hot water.
Your boiler is struggling to get the correct mix of air needed to burn the gas safely and efficiently.
Your boiler is experiencing a communication problem with its internal temperature sensor, causing it to shut down unexpectedly from time to time.
Your boiler has detected a poor connection within its internal wiring, which is preventing it from communicating properly and stopping it from operating.
Your boiler's main electronic brain has encountered an internal error and has stopped the system from running to prevent potential damage.
Your boiler has shut down because it is not burning fuel efficiently or safely, which is usually caused by a faulty internal sensor or an incorrect gas mixture.
Your boiler has become too hot and has automatically shut itself down to prevent damage or safety issues.
Your boiler is struggling to breathe because it cannot safely push exhaust gases out through the flue pipe.
Your boiler is failing to detect the flame needed to heat your home, so it has safely shut down to prevent gas from building up.
Your boiler has stopped working because the fan cannot properly push exhaust fumes out or pull fresh air in through the flue pipe.
Your boiler has stopped working because it is not receiving a supply of oil to create a flame.
Your boiler is failing to light the burner, meaning it cannot produce heat or hot water.
Your boiler has lost all electrical power, meaning it cannot start up to provide you with any heating or hot water.
BoilerFaultCodes