What does the Johnson Starley E03 fault code mean?

Your boiler has shut down because it has reached an unsafe temperature and needs to cool down before it can be reset.

How much does it cost to fix Johnson Starley error code E03?

Typical repair cost for the Johnson Starley E03 fault is £100-220 including labour.

Check that all radiator valves are fully open

High limit thermostat open

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.

Each noise points to a different fault.

Work through these before the call-out.