High
Mains LED flashing on Baxi 800 Heat (range)

Your boiler's control panel is not receiving a signal, which is preventing it from firing up to provide your heating and hot water.

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.

What the manual says

Manufacturer manual

Control knob is not on, or fault in wiring between control PCB and interface PCB / faulty control PCB.

From this model's manual
Verified against the Baxi Boiler 100 He installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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