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A08

Vokera fault code

Vokera A08: return thermistor fault

Engineer only

The sensor that measures the temperature of water returning to the boiler has a fault.

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: Vision and Compact A. Codes can differ between models, so check your manual.

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

Model	Meaning
Vision and Compact A	Return thermistor fault

Can I fix A08 myself?

No. A sensor fault needs a Gas Safe registered engineer.