What does the Keston E 12 fault code mean?

Your boiler has detected that it is getting dangerously hot and has shut itself down to prevent damage to the internal system.

How much does it cost to fix Keston error code E 12?

Typical repair cost for the Keston E 12 fault is £150-300 including labour.

Thermal fuse blown or flue overheat thermostat activated.

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Work through these before the call-out.

Each noise points to a different fault.

Lockout fault with a reset-needed pattern.