If your Worcester Bosch boiler is showing U9, it may not be a conventional fault code. On certain older Worcester Bosch Greenstar CDi boilers with a two-character display, U0 to U9 represent temperatures from 100°C to 109°C. This means U9 shows that the boiler flow temperature has reached 109°C. A U9 display does not identify…
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If your Viessmann Vitodens 100-W boiler is showing an FF fault code, the boiler has entered a safety lockout and needs attention. On Vitodens 100-W models that use this fault-code format, FF usually means the burner has been blocked because the boiler has detected a fault in the burner control circuit. This can involve the…
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The Viessmann F2 fault code usually means the boiler has gone into a safety lockout because it has detected an overheating or temperature-limiter issue. On many Viessmann Vitodens boilers, this can be linked to poor water circulation, trapped air, low system pressure, a pump problem, or a fault with the temperature limiter itself. The exact…
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The Viessmann F4 fault code commonly appears when a boiler cannot confirm that a burner flame has been established and enters a safety lockout. On several Vitodens models, F4 is listed as a “no flame signal” fault. However, Viessmann says fault-code meanings can vary by boiler model, and on some Vitodens gas boilers an F4…
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If your boiler has stopped working and is displaying one of the Glowworm fault codes, don’t panic. These fault codes are built into the boiler to help identify problems quickly, making it easier to troubleshoot minor issues or determine when professional assistance is needed. Some faults can be resolved with simple checks, such as topping…
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If your boiler is displaying the Glowworm F75 fault code, don’t panic. While this error can prevent your heating and hot water from working, it doesn’t necessarily mean your boiler needs replacing. The Glowworm F75 fault code is one of the more common faults found on Glow-worm boilers. In many cases, it’s linked to a…
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If your boiler is displaying the Glowworm F25 fault code, it indicates a circulation fault. This means your boiler cannot circulate hot water effectively through your central heating system. As a safety measure, the boiler shuts down to prevent overheating and potential damage. While some causes of the Glowworm F25 fault code can be resolved…
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If your boiler has stopped working and is showing an Alpha E8 fault code, particularly E8, it means the system has reached the maximum number of reset attempts. This is a built-in safety feature designed to prevent damage or unsafe operation. The good news? In many cases, this issue can be diagnosed and sometimes resolved…
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If your boiler has suddenly stopped working and is displaying the Alpha E20 fault code, it usually points to a flame sensing fault or ignition failure. This means the boiler cannot detect a flame during operation, so it shuts down as a safety precaution to prevent gas buildup. In this guide, we’ll break down the…
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If your boiler suddenly stops working and displays an error, understanding Vokera fault codes can help you quickly identify the issue and take the right action. Vokera boilers are known for reliability, but like any heating system, they can develop faults. These codes are designed to pinpoint specific problems, ranging from minor issues you can…
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