What does the Saunier Duval 1 8 fault code mean?

Your boiler has detected that the water inside the unit is dangerously overheated, so it has safely shut itself down to prevent damage.

How much does it cost to fix Saunier Duval error code 1 8?

Typical repair cost for the Saunier Duval 1 8 fault is £150-250 including labour.

The heating flow thermistor is detecting a temperature in excess of 100°C.

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

Each noise points to a different fault.

Lockout fault with a reset-needed pattern.

Sludge build-up — needs flushing, not bleeding.