High Lockout
C2849 on Grant Vortex

Your boiler has stopped working because of a communication failure between its internal electronic brains and a fault in the ignition system.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Fault C; Chassis CodeProblem is controller area network wiring bus and modules.fault two; MFG – Manufacturer SpecificFault eight; Ignition System Or Misfirefault four; BBV Sensor Circuit Low Voltagefault nine; Kick-Down Switch Failed Short

What causes this fault?

This fault occurs when the boiler's internal computer loses the ability to talk to the ignition components due to an electrical communication break. The most common reason is a hardware failure in the main control board or a loose connection in the internal wiring, which prevents the boiler from safely starting the burner.

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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