High
DHW Flow Switch section on Baxi Combi 80e

Your boiler is failing to detect when the hot water is turned on, meaning the system won't fire up to heat the water for your taps.

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

LED 1: Flash, LED 2: On, LED 3: On, LED 4: Off

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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