What does the Potterton neon flashing (2nd instance) fault code mean?

Your boiler is receiving conflicting signals about whether it should be running, which is causing it to restart its warm-up cycle repeatedly.

How much does it cost to fix Potterton error code neon flashing (2nd instance)?

Typical repair cost for the Potterton neon flashing (2nd instance) fault is £120-250 including labour.

Preheating function starts after 25 seconds. Preheat control is not at minimum position. External control calling for heat. Go to section ‘L’.

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Almost always a stuck diverter valve on combis.

Work through these before the call-out.

Safety-critical — turn off, read this.