High
E28 on Potterton Titanium Combi

Your boiler has detected an issue with the system that removes waste gases, meaning it has safely shut down to prevent any unsafe conditions.

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

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

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 →

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