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 29 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.
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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
- 630 COMBI LPG
- 636 COMBI
- 636 COMBI LPG
- 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 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 12 System ErP
- Ecoblue 15 System ErP
- Ecoblue 24 System ErP
- Ecoblue 28 System ErP
- Ecoblue Advance Combi Repair: £150-250
- EcoBlue System Repair: £150-250
- Ecoblue18 System ErP
- PLATINUM COMPACT 25 COMBI
- PLATINUM COMPACT 30 COMBI
- PLATINUM COMPACT 36 COMBI
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 31 August 2026