Medium
S.98 on Vaillant Combi Compact 282EB

Your boiler is temporarily pausing because it has noticed an unusual difference in temperature readings and needs to double-check its internal sensors before starting up again.

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

Flow return sensor check is running demand is block

Engineer required

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

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Related fault codes

F.22View →F.23View →F.24View →

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