27 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
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Your boiler has failed to ignite, meaning it cannot detect a flame to safely start heating your home.
Your boiler has failed to ignite its burners, meaning you currently have no heating or hot water.
Your boiler has detected an issue with the internal fan or its wiring, which prevents it from safely igniting and providing heating or hot water.
Your boiler has stopped working because it is not receiving enough gas pressure to run safely.
Your boiler has detected an internal error message, which usually means the system needs to be reset or checked by a professional.
Your Viessmann boiler has detected a combustion or flue gas issue, meaning it has safely shut down to prevent any unsafe operation.
Your Viessmann boiler has detected an internal communication or electronic control error and has locked itself out to ensure safety.
Your boiler has temporarily stopped working because it has detected an internal limit or safety temperature has been reached.
Your boiler has detected an internal control error and has safely stopped working to prevent further issues.
Your boiler has stopped working because it failed to ignite properly or maintain a steady flame.
Your boiler has detected an issue with the air supply or exhaust removal, meaning it has safely shut down to prevent any harmful gases from escaping.
Your Viessmann boiler has registered an internal safety fault that has stopped it from operating normally.
Your boiler has detected an internal electronic or sensor issue and has stopped working to keep your home safe.
Your boiler has detected an internal communication or control board error and has stopped working to keep you safe.
Your boiler has detected an issue with its outside temperature sensor, which helps it regulate the heating levels automatically.
Your boiler has detected an internal communication or control system fault and has temporarily stopped working to keep you safe.
Your boiler has detected an internal safety sensor fault and has safely locked itself out to prevent further issues.
Your Viessmann boiler has detected an internal communication or sensor error, resulting in a safety shutdown that stops your heating and hot water.
Your boiler has detected an issue with the outside temperature sensor, meaning it may not properly adjust to changes in the weather.
Your boiler has detected an internal communication or sensor error and has temporarily stopped working to keep you safe.
Your boiler has detected an internal communication or sensor issue, which has temporarily stopped it from working safely.
Your boiler has detected an internal communication or sensor fault that is preventing it from operating correctly.
Your boiler has detected an internal communication or operational fault and has safely locked itself out to prevent further issues.
Your boiler has detected an internal communication or flame detection issue that has temporarily stopped it from working safely.
Your Viessmann boiler has detected an internal communication or control board fault and has stopped operating for safety.
Your boiler has registered an internal electronic fault that has temporarily stopped it from working safely.
Your boiler has registered an internal electronic fault that is preventing it from running safely and efficiently.
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BoilerFaultCodes