High
E 30 on Ideal Imax W

Your boiler is struggling because it cannot move the hot water away from the heating unit quickly enough, leading to a significant temperature difference between the outgoing and returning water.

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

Flow/return temperature differential too high

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

E 28View →E 31View →

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