Medium
Er.13 on Vaillant Turbomax Pro 28 2E

Your boiler is struggling to switch between heating your radiators and heating your hot water taps, which may cause your hot water to stop working or your radiators to get hot when they shouldn't.

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

Diverter valve

Engineer required

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

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