High
E14 on Alpha CD24

Your boiler has detected that water is not circulating through the system correctly, causing a heat imbalance that has prompted the unit to shut down for safety.

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

Temperature difference between flow and return NTCs 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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