Low
r1 on Worcester Bosch Greenstar 25i (ZWB 7-25)

Your boiler has reverted its custom settings back to the manufacturer's original factory defaults, meaning you may need to re-adjust settings like your heating temperature.

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.

What the manual says

Manufacturer manual

Reset 1: Resetting service functions 0.0 to 4.9 to their factory settings

From this model's manual
Verified against the Worcester Bosch Greenstar 25i Zwb 7 25 installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Navigate to the boiler's menu and check your heating and hot water temperature settingsAdjust the settings to your preferred temperaturesMonitor the boiler to ensure it continues to operate correctly

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Boiler cover options

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