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88:1 on Viessmann Vitodens 300-W

Your boiler's control panel has switched from Celsius to Fahrenheit, meaning temperatures are being displayed using a different measurement system rather than showing a mechanical fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Temperature display in Fahrenheit

What causes this fault?

This happens when the boiler's internal control unit has been adjusted to display temperature units used in the United States rather than the UK standard. It is usually triggered by someone accidentally changing the display settings within the user menu or during a recent service. It does not indicate a mechanical failure or a safety risk to your heating system.

DIY fix possible

Navigate to the boiler's settings menu using the control dial or touch interface.Look for the 'Display' or 'Configuration' sub-menu.Locate the temperature unit setting and change it back from '°F' to '°C'.

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