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BoilerCodes
F.65
Vaillant fault code

Vaillant F.65: electronics temperature fault

Engineer only

Vaillant describes F.65 on ecoTEC plus boilers as: electronics temperature fault. Possible causes Vaillant lists, for an engineer to check: electronics overheating due to external influences, electronics defective.

What you can safely do

There is nothing you can safely do yourself with this one. Leave the boiler off and book an engineer.

Call a Gas Safe engineer if

  • Book a Gas Safe registered engineer.
Find a Gas Safe engineer near you Opens the official Gas Safe Register search.

Applies to: ecoTEC plus. Codes can differ between models, so check your manual.

What F.65 means on each Vaillant model

From Vaillant's own fault tables. Your model name is usually on the front of the boiler or in the user manual.

ModelMeaningCauses listed for engineers
ecoTEC plusElectronics temperature faultElectronics overheating due to external influences, electronics defective

Common questions about Vaillant F.65

Can I fix Vaillant F.65 myself?

No. It needs a Gas Safe registered engineer to diagnose. Tell them the exact code and your boiler's model name.

Nearby Vaillant codes

See all 36 Vaillant codes

Sources