High
E28 on Baxi Duo-tec Combi ErP

Your boiler is struggling to clear exhaust gases safely and has turned itself off to prevent a potential hazard.

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

Flue NTC Fault, Air Pressure Switch Fault, Blocked Flue, Blocked Condensate or Wiring Fault

From this model's manual
Verified against the Baxi Duo Tec Combi Erp installation & service manual, page 47.
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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