BoilerFaultCodesYour boiler has detected an unusual temperature reading or a data processing error and has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Technical error data cycle (t1/t2 temperatures) as observed in error memory display
What causes this fault?
This fault occurs when the boiler's internal computer detects a conflict between the temperature readings on the flow and return pipes. It is usually caused by a physical failure of the temperature sensors or a communication glitch on the main circuit board that prevents the boiler from safely monitoring heat levels. In some cases, damaged internal wiring can also disrupt these signals, leading the system to shut down for protection.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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