Unknown
E12 on Vaillant ecoMAX 824E

Vaillant ecoMAX 824E fault code E12

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Water deficiency error – Appliance blocked

From this model's manual
Verified against the Vaillant/Vaillant Ecomax 824e installation & service 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 26 fault codes on the ecoMAX 824E

Seeing a different code? Every code this model can display, in one place.

0123456789E11E13F00F04F05F10F14F15F20F21F22F23F26F32F40

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