13 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
Replaced by: Potterton Promax HE System
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Your boiler is struggling to detect the weather outside, so it is defaulting to a standard operating mode.
Your boiler has stopped working because a sensor that measures the water temperature is not sending a signal, causing the system to shut down as a precaution.
Your boiler is currently unable to accurately measure the temperature of the water it is heating, so it has stopped working as a safety precaution.
Your boiler has detected that it is getting too hot and has automatically shut down to prevent damage or dangerous overheating.
Your boiler has detected that the flame inside has gone out unexpectedly while it was trying to heat your water or home.
Your boiler has detected that the internal fan is moving too slowly to safely clear exhaust gases, so it has stopped working as a safety precaution.
Your boiler is failing to light because it is either not receiving enough gas or your room thermostat is preventing it from turning on.
Your boiler is failing to ignite because it is not receiving a reliable supply of gas.
Your boiler's internal computer is experiencing a communication fault, which has caused it to stop working for your own safety.
Your boiler is displaying this message simply because the reset button was pressed when there was no actual problem to fix.
Your boiler's internal computer is experiencing a communication or processing error that has caused the system to shut down for safety.
Your boiler is failing to start because it cannot detect that its internal fan is spinning fast enough to safely clear exhaust gases.
Your boiler has stopped working because it cannot detect that water is flowing correctly through the system.
BoilerFaultCodes