BoilerFaultCodesWhat the manual says
Manufacturer manualCONTROL/NO FLOW THERMISTOR FAULT
From this model's manual
Verified against the Ideal/Ideal Logic Max System 4179613 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. It is usually caused by the sensor itself failing due to age, or a loose connection in the internal wiring preventing the computer from reading the temperature accurately.
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 38 fault codes on the Logic Max System
Seeing a different code? Every code this model can display, in one place.