BoilerFaultCodesTechnical 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 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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