Medium
F15 on Vaillant ecoMAX 828E

Your boiler has detected an electrical fault with the sensor that measures the temperature of your hot water, meaning it cannot properly regulate your hot water supply.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Short circuit of DHW heat exchanger NTC (NTC3)

From this model's manual
Verified against the Vaillant/Vaillant Ecomax 828e 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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Related fault codes

F10View →F11View →F12View →F13View →F14View →

All 26 fault codes on the ecoMAX 828E

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

0123456789E11E12E13F00F04F05F10F14F20F21F22F23F26F32F40

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