High Lockout
e44 on Remeha Avanta Plus 35c

Your boiler's internal computer has detected an error in its configuration settings and needs a professional to reset internal parameters.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Parameter check. Automation settings.

What causes this fault?

This fault occurs when the boiler's control board loses or fails to recognise its specific identity and operating instructions. The most common reason is a communication failure between the main circuit board and the small plug-in 'key' that stores the boiler's settings, often caused by a power surge or an internal electronic glitch.

Engineer required

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

Find a Gas Safe engineer
Search the official register →

Related fault codes

E36View →E43View →E45View →

Related guides you might find useful

Boiler keeps cutting out

Lockout fault with a reset-needed pattern.

Read →

Yellow or orange flame — CO safety

Safety-critical — turn off, read this.

Read →

When to replace your boiler

7 signs repair isn't worth it anymore.

Read →