Medium
Block 86 on Atag E Range

Your boiler has detected that the electricity supply coming into your home is unstable or fluctuating outside of normal limits.

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

The frequence of the power supply deviates more than 2,5Hz (<47,5Hz, >52,5Hz)

Engineer required

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

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Related fault codes

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