High
AL74 on Vokera Mynute Vhe

Your boiler is struggling to move water through your heating system, which means it has stopped heating your home to prevent itself from overheating.

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

No water circulation

Shared across the Mynute range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
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 sensors detect that heated water isn't moving away from the heat exchanger quickly enough. The most common reasons are a mechanical failure of the circulation pump, a build-up of sludge blocking the pipes, or a faulty sensor providing incorrect temperature readings. To prevent the unit from overheating, the system shuts down as a safety precaution.

This issue often surfaces when the heating is first turned on after summer, as the pump can seize up after long periods of inactivity.

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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Related fault codes

All 20 fault codes on the Mynute Vhe

Seeing a different code? Every code this model can display, in one place.

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