High
E23 on Heatline Sargon 30

Your boiler's computer is struggling to read its own configuration settings, which is preventing it from starting up correctly.

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.

What the manual says

Manufacturer manual

Invalid parameter board

Referenced from a related model
This code was carried over from a closely related model. Treat it as a guide and confirm against your boiler’s own manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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

E22View →E24View →

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