High
05 on Vokera Mynute 28E / 35E

Your boiler has detected a critical internal error that prevents it from starting up safely.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Boiler fault. Call engineer.

From this model's manual
Verified against the Vokera Mynute 28e 35e installation & service manual, page 47.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the boiler's internal computer experiences a critical communication failure or an electrical component on the board burns out. It is often caused by long-term wear and tear, power surges, or moisture ingress affecting the delicate circuitry. Because the board can no longer monitor safety sensors reliably, the boiler shuts down as a protective measure.

This issue often comes to light during the first cold spell of autumn when the boiler is suddenly under high demand after being idle all summer.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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