High Lockout
E38 on Vokera Pinnacle

Your boiler has experienced an internal communication error or hardware failure within its control system, causing it to shut down for safety.

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

Internal fault

What causes this fault?

This fault occurs when the boiler's internal computer system suffers a communication breakdown, meaning the various components can no longer talk to each other correctly. It is usually caused by a hardware failure within the main control board or damage to the connecting wires that carry signals throughout the unit. Because the boiler can no longer verify that it is operating safely, it will shut down immediately to prevent any damage.

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

E37View →

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 →