How much does it cost to fix Vokera error code 40?

Typical repair cost for the Vokera 40 fault is £80-180 including labour.

40 Medium

Vokera 40 Fault Code

Q: What does the Vokera 40 fault code mean?

Your boiler has detected a temporary internal communication or sensor timing error and is essentially waiting to see if it clears itself.

The Vokera 40 fault code means: your boiler has detected a temporary internal communication or sensor timing error and is essentially waiting to see if it clears itself.. It appears on 4 Vokera models in our database.

Technical description: Temporary fault code (Refer to section 7.10)

What causes the Vokera 40 fault?

This fault occurs when the boiler's internal electronics detect a brief interruption or a glitch in the data being sent between sensors. The most common cause is a sensor that is starting to wear out or a small electrical disturbance on the main control board that makes the system pause to re-check its readings.

Typical repair cost £80-180 (including labour)

DIY fix possible

Monitor the boiler to see if the code clears automaticallyPress the reset button if the code remains or turns into a lockoutEnsure power to the boiler has not been interrupted or fluctuated

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Vokera models that show the 40 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Vokera 40 fault code information on this page is sourced and cross-checked against the official Vokera service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026