High Lockout
E36 on Vokera Condexa Pro

Your boiler's computer memory has developed a communication fault and can no longer process its stored settings.

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

EEPROM reading error

What causes this fault?

This fault occurs when the boiler's main control board loses the ability to read the permanent memory chip that stores its essential operating data. It is usually caused by a hardware failure within the electronics, often triggered by age or a sudden electrical power surge. Because the boiler no longer knows its safe operating parameters, it shuts down entirely as a safety precaution.

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.

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Related fault codes

E 34View →E 37View →E 42View →

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