High
DHW FLOW SWITCH on Baxi Combi 80e

Your boiler thinks a hot water tap is turned on even when it isn't, which is preventing the system from working correctly.

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

Switch blocked or lack of continuity across W on 5-way connector when taps are off.

From this model's manual
Verified against the Baxi Combi 80e 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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