High Lockout
T.05 on Vaillant ecoTEC Plus 832

Your boiler's internal pump is having trouble moving water through the system, which is preventing it from providing heating or hot water.

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.

Technical description

Circulation pump

What causes this fault?

This fault occurs when the boiler's internal pump fails to circulate water effectively through the heat exchanger. The most common reasons are a mechanical failure of the pump motor, a buildup of sludge blocking the internal components, or air trapped within the unit preventing the pump from turning.

This fault is frequent in autumn when heating systems are switched back on after a summer of inactivity, which can cause the pump to seize.

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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