Medium
Er.7 on Vaillant Turbomax Pro 28 2E

Your boiler's internal tank that handles pressure changes is likely losing its charge or leaking, which can lead to system pressure spikes.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Expansion vessel 10 l

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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