Medium
B02 on Ariston Euro Prisma 24

Your boiler is not communicating correctly with your wall thermostat, meaning the heating may not turn on when you want it to.

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

Room Thermostat

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 if your wall thermostat is turned up high enough to call for heat.Replace the batteries in your wireless thermostat or programmer.Ensure the thermostat is not blocked by furniture or located in a very cold draught.

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