15 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has detected that water is not circulating properly through the system, which triggers a safety lock to prevent internal damage.
Your boiler's internal sensor that detects water movement has developed an electrical fault, causing the system to stop working as a precaution.
Your boiler has stopped working because it is unable to accurately measure the temperature of the water inside it, causing it to shut down for safety.
Your boiler is struggling to detect the water flowing through it, which is preventing it from safely firing up your heating or hot water.
Your boiler has detected that it is running too hot and has automatically shut itself down to prevent damage.
Your boiler has detected an internal communication or electronic fault on its main control board, meaning it cannot safely start up.
Your boiler has detected an internal electrical power supply issue, meaning it has shut down to keep your home safe.
Your boiler has detected an issue with the internal fan that safely removes combustion gases, so it has automatically shut down to prevent any risk.
Your boiler has detected an issue with the valve that controls the supply of gas inside the appliance, causing it to safely lock out.
Your boiler has detected an issue with the internal observation window that allows engineers to check the flame, which prevents the unit from firing up safely.
Your boiler is having trouble detecting the burner flame safely, which has caused it to stop working to protect your home.
Your Potterton boiler has detected a critical internal fault with the main burner assembly and has safely shut down to prevent unsafe operation.
Your boiler has detected an issue with the internal component that transfers heat to your water, and it has automatically shut down for safety.
Your boiler has stopped working because it has tried to light several times but failed to detect a flame.
Your boiler has temporarily stopped working because it has detected an issue with the internal water flow and circulation system.
BoilerFaultCodes