What does the Saunier Duval E21 fault code mean?

Your boiler has stopped working because the water pressure is too low for the system to operate safely.

How much does it cost to fix Saunier Duval error code E21?

Typical repair cost for the Saunier Duval E21 fault is £0-120 including labour.

Locate the filling loop (usually a silver flexible hose) underneath the boiler.

Lack of water (low pressure)

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

Six most common causes of dropping pressure.

Step-by-step using the filling loop.

7 signs repair isn't worth it anymore.