Medium
B08 on Ariston Euro Prisma 24

Your boiler has lost its connection to the external timer or there is a communication error with its internal clock settings.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Time Clock

From this model's manual
Verified against the Ariston Euro Combi 30 Mffi 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

Check that the timer or programmer is switched on and displaying a time.Ensure any batteries in a wireless thermostat or timer have been replaced.Try resetting the boiler by pressing the reset button for five seconds.

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