High
E28 on Baxi Suprima 30

Your boiler has detected a problem with how it disposes of waste gases or a sensor error, causing it to shut down for safety.

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

Error with the NTC (Negative Temperature Coefficient) flue, air pressure switch or blocked flue or condensate

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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Related fault codes

E50View →E160View →E133View →

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