High
0 then 8 on Saunier Duval Ecosy

Your boiler has detected that waste water cannot drain away properly, likely due to a blockage or frozen external pipe, causing it to shut down for safety.

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

As a safety feature the boiler will stop working if the condensate drain becomes blocked. (May be due to ice in freezing conditions).

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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