BoilerFaultCodesBaxi 28 Fault Code
The Baxi 28 fault code means: your boiler is struggling to accurately detect the temperature of the water used for your taps and shower, which will likely result in no hot water or fluctuating temperatures.. It appears on 23 Baxi models in our database.
Technical description: Fault on Hot Water Sensor
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Avoid the next call-out bill
A cover plan would handle faults like 28: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.
Baxi models that show the 28 fault code
Click a model for the full fault code list and model-specific repair notes.
- 105e Repair: £120-200
- 124 Combi Repair: £120-£220
- 200 / 400 Combi Repair: £150-250
- 600 Combi (range) Repair: £120-190
- 624 Combi Repair: £100-£180
- 825 Combi Repair: £100-£180
- Assure Repair: £150-250
- Bahama 80e / 105e Repair: £90-160
- Combi 105 HE Repair: £120-200
- Combi 130 HE Repair: £90-160
- Combi 80 Maxflue Repair: £90-160
- Combi 80e Repair: £90-160
- Combi Elite Repair: £90-160
- Combi Instant 80/105 HE Repair: £120-200
- Duo-tec Combi ErP Repair: £150-300
- Duo-tec Combi GA Repair: £120-£200
- Duo-tec Combi HE A Repair: £120-220
- EcoBlue Repair: £150-250
- Ecoblue Advance Combi Repair: £150-250
- EcoBlue Advance Heat Repair: £100-£190
- EcoBlue Heat Repair: £120-220
- EcoBlue Plus Combi Repair: £120-£200
- EcoBlue System Repair: £150-250
Source
Baxi 28 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