BoilerFaultCodes.com

Potterton Assure Combi and System Fault Codes

CombiSystem Natural GasLPG 25-36 kW 2018-present
GC Numbers: 47-393-5447-393-5547-393-5641-393-4841-393-49

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Most common fault codes

E09
Your boiler has lost communication with its gas control unit, meaning it cannot safely ignite to provide heating or hot water.
Gas Safe engineer required · £120-280
E12
Your boiler is struggling to pump water around the system, often because the water pressure is too low or there is a blockage or air bubble preventing flow.
May be DIY safe · £100-250
E13
Your boiler has detected that water is still circulating or a sensor is stuck even when the pump should be off.
Gas Safe engineer required · £120-250

All 28 fault codes

Code Severity Plain English
E09 High Your boiler has lost communication with its gas control unit, meaning it cannot safely ignite to provide heating or hot water.
E10 Low Your boiler has lost signal from the sensor that monitors the temperature outside your home, usually because of a wiring fault or a broken sensor.
E12 High Your boiler is struggling to pump water around the system, often because the water pressure is too low or there is a blockage or air bubble preventing flow.
E13 High Your boiler has detected that water is still circulating or a sensor is stuck even when the pump should be off.
E15 High Your boiler has detected an electronic communication error with the gas valve, meaning it cannot safely light the burner to provide heat or hot water.
E20 High Your boiler has lost its ability to accurately measure the temperature of the water used to heat your radiators, meaning your heating will likely stop working.
E28 High Your boiler has stopped working because a sensor that monitors the temperature of the exhaust gases has failed or is reporting an error.
E40 High Your boiler has detected an issue with the sensor that monitors the temperature of the water returning from your radiators.
E50 Medium Your boiler's temperature sensor for hot water has developed a fault or a loose connection, meaning the system cannot accurately measure how hot the water is.
E109 High Your boiler has detected that water is not circulating correctly before the burner lights, which usually means there is a blockage or a pump issue.
E110 High Your boiler has shut down because it grew too hot too quickly, usually because the water inside isn't circulating properly.
E118 High Your boiler has detected that there is not enough water pressure in the system to operate safely, causing it to shut down.
E125 High Your boiler is struggling to move heated water through the system effectively, which is causing it to stop for protection.
E128 High Your boiler has lost its flame multiple times during operation and has safely shut down to prevent a malfunction.
E129 High Your boiler is starting up but struggling to keep the flame alight, causing it to shut down for safety purposes.
E130 High Your boiler has shut down because a safety sensor has detected that the exhaust gases are getting too hot, which can be caused by a blockage or an internal component failure.
E133 High Your boiler has failed to light a flame, which is usually caused by a temporary interruption in the gas supply or a frozen condensation pipe.
E134 High Your boiler is trying to start but cannot detect a flame, meaning it is failing to ignite after several attempts.
E135 High Your boiler has lost its gas supply or detected an internal error, causing it to shut down for safety.
E154 High Your boiler has detected that water is circulting poorly or heating up too quickly, causing the temperature sensors to provide unusual readings.
E160 High Your boiler has detected an issue with its internal fan, which means it cannot safely exhaust fumes and has stopped working as a safety precaution.
E163 Medium Your boiler has detected a problem with the sensor that monitors the temperature of your hot water, meaning you likely have no hot water or it is inconsistent.
E270 High Your boiler has detected that there is not enough water circulating inside it while the burner is on, causing it to overheat rapidly and shut down for safety.
E317 High Your boiler has detected an issue with the electrical frequency coming from the mains power supply or a fault within its internal control board.
E321 Medium Your boiler has detected an issue with the sensor that monitors the temperature of your hot water, meaning your taps may not get warm.
E384 High Your boiler thinks a flame is present even though it hasn't been told to light, causing the system to shut down for safety.
E385 High Your boiler is not receiving enough electrical power from the mains supply to operate safely.
E430 High Your boiler has detected that the water pressure is too low to operate safely and has temporarily stopped working.

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