Unknown
F.89 on Vaillant ecoFIT sustain 415

Vaillant ecoFIT sustain 415 fault code F.89

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Incorrect pump detected. Unsuitable pump connected, PWM plug not plugged in or has come loose, multiple plug on the PCB not plugged in correctly, interruption in cable harness, electronics defective

From this model's manual
Verified against the Vaillant/Vaillant Vaillantpro Ecofit Sustain Open Vent Installation And Servicing 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 36 fault codes on the ecoFIT sustain 415

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

conF.00F.01F.10F.11F.13F.22F.23F.24F.25F.27F.28F.29F.32F.49F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.83F.85F.87F.88F.97

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