High
E42 on Remeha Avanta Plus 28c

Your boiler is struggling to circulate water properly because there is either not enough water in the system or a blockage is preventing it from flowing through the pipes.

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

Low water flow: delta T between flow and return too high or low water level

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

E10View →E40View →E2View →

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