Medium
F 0t on Ideal Independent System2 S15

Your boiler has lost communication with the wall thermostat, meaning it cannot receive the signal to turn your heating on.

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 Fault: Check Room Stat & connections

From this model's manual
Verified against the Ideal Independent System2 S15 installation & service manual, page 48.
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 has run out of batteries and replace them if necessary.Ensure the thermostat is turned up higher than the current room temperature.If using a wireless model, ensure the receiver box is powered on and within range of the thermostat.

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