Smell gas? Leave the property and call the National Gas Emergency line on 0800 111 999

F.63

Vaillant fault code

Vaillant F.63: EEPROM fault

Engineer only

Vaillant describes F.63 on ecoTEC plus boilers as: eEPROM fault. Possible causes Vaillant lists, for an engineer to check: 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.

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.

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

Model	Meaning	Causes listed for engineers
ecoTEC plus	EEPROM fault	Electronics defective

Can I fix Vaillant F.63 myself?

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