Low
A42 on Vokera Vibe MAX S

Your boiler has detected that the water pressure is getting too low and needs to be topped up to continue working properly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Fill the system (transitional)

From this model's manual
Verified against the Vokera Vibe Max S 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.

DIY fix possible

Locate the filling loop valves underneath the boiler.Slowly open both valves to allow water into the system.Monitor the pressure gauge until it reaches between 1.0 and 1.5 bar, then close both valves tightly.

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Related fault codes

A41View →A40View →F41View →

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