High
E41 on Ravenheat TS 90

Your boiler has detected that water is not circulating correctly through your radiators and pipework, causing an unusual temperature difference.

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

Different flow/return temperatures

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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