High
ER 12 + SPANNER on Johnson Starley Warmcair DW

Your boiler's internal sensor has detected an unusual temperature reading on the pipe returning from your radiators, suggesting a sensor fault or water flow issue.

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

CH return temp sensor out of range

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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