High
B07 on Ariston Microsystem 15

Your boiler is struggling to switch between heating your radiators and providing hot water, which means you will likely have no hot water or central heating until it is fixed.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Microswitch for Diverter Valve

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

B02View →

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