Low
d19 on Alpha E-Tec S

Your boiler is displaying an internal software diagnostic screen, which usually means the system is performing a self-check or has encountered a minor glitch in its display settings.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Toggles between safety software version / functional software version n/a

From this model's manual
Verified against the Alpha E Tec S installation & service manual, page 33.
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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

d18View →d20View →

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