BoilerFaultCodesWhat the manual says
Manufacturer manualFlow Thermistor Fault
From this model's manual
Verified against the Ideal/Ideal Hub Ideal Classic 24 30 35 Installation Servicing Instructions Manual installation & service manual.
What causes this fault?
This fault occurs when the boiler's control system receives an incorrect or missing signal from the sensor that monitors hot water leaving the unit. The most common reason is that the sensor has physically failed or developed a loose electrical connection, meaning the boiler can no longer safely regulate its temperature.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Related fault codes
All 19 fault codes on the Logic Max Combi
Seeing a different code? Every code this model can display, in one place.