BoilerFaultCodesBaxi E28 Fault Code
The Baxi E28 fault code means: your boiler is currently unable to sense the temperature of your hot water, so it has stopped producing it to prevent potential overheating.. It appears on 9 Baxi models in our database.
Technical description: Hot Water NTC Fault
What causes the Baxi E28 fault?
This fault occurs when the boiler's internal safety sensors detect that the exhaust gases are too hot or cannot escape the property correctly. It is often triggered by a breakdown in the sensor that monitors flue temperatures, or a physical blockage in the pipe that carries waste water away from the unit. When the system can no longer safely vent heat or clear condensation, it shuts down to prevent internal damage.
This fault is significantly more common during freezing winter temperatures, as the external condensate drainage pipe can freeze solid and cause a backup into the boiler.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Baxi models that show the E28 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Baxi E28 fault code information on this page is sourced and cross-checked against the official Baxi service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026