7 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has temporarily stopped working because it cannot accurately measure the temperature of the water flowing through the system.
Your boiler is temporarily locked out because it is receiving an incorrect temperature reading from the pipe returning water back into the system.
Your boiler has lost connection to the weather sensor outside your home, meaning it can no longer automatically adjust your heating based on the outside temperature.
Your boiler has detected that the pipes carrying water in and out of the system have been installed the wrong way around.
Your boiler's hot water cylinder sensor is not working properly, which means it cannot accurately monitor the temperature of your stored hot water.
Your boiler has paused because an external safety device, such as a room thermostat, fire safety valve, or system interlock, has been triggered or disconnected.
Your boiler has temporarily locked out because it mistakenly detects a flame when it shouldn't be burning.
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BoilerFaultCodes