What does the Ariston A03 fault code mean?

Your boiler has failed to light after several attempts and has locked itself out for safety.

How much does it cost to fix Ariston error code A03?

Typical repair cost for the Ariston A03 fault is £100-350 including labour.

Check that your gas emergency control valve is open and you have credit on your gas meter

After this [E04 attempts], should the boiler still not sense a flame, error code A03 will appear on the LCD.

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

Lockout fault with a reset-needed pattern.

Older boilers — thermocouple, draught, gas supply.

7 signs repair isn't worth it anymore.