Medium
F 0t on Ideal Logic SYSTEM2 S15

Your boiler is failing to communicate with your wall-mounted thermostat, which is preventing it from knowing when to turn the 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/Ideal Logic System 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 thermostat requires new batteries and replace them if necessaryEnsure your thermostat is switched on and within signal range of the boiler receiverTurn the boiler off at the fused spur for 60 seconds and then back on to reset the connection

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Related fault codes

F 01View →L 01View →

All 27 fault codes on the Logic SYSTEM2 S15

Seeing a different code? Every code this model can display, in one place.

F 0UF 01F 02F 02 or FN or LNF 03F 04F 04 or L 04F 05F 05 or L 05F 06F 07F 09F 10F 12F 13F 14F 15F 16F 17L 0CL 0dL 01L 02L 04L 05L 06

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