BoilerFaultCodesWorcester Bosch E2 Fault Code
The Worcester Bosch E2 fault code means: your boiler has detected a faulty internal temperature sensor, which means it cannot accurately measure how hot the water is and has stopped running for safety.. It appears on 39 Worcester Bosch models in our database.
Technical description: Flow sensor short circuit - Flow sensor shorted or damaged.
What causes the Worcester Bosch E2 fault?
This fault occurs when the boiler's internal thermometer, which monitors the temperature of the water leaving the unit, fails or sends an incorrect signal to the control board. The most common reason is that the sensor has physically degraded over time or suffered an electrical short, meaning the boiler can no longer safely regulate its heat output. In some cases, the issue may also be caused by damaged or loose wiring connecting the sensor to the main computer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A cover plan would handle faults like E2: no call-out fees, no surprise bills.
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Worcester Bosch models that show the E2 fault code
Click a model for the full fault code list and model-specific repair notes.
- 24/28/35 CDi MkII Repair: £150-250
- 35 RSF Repair: £90-160
- 532 / 537 / 542 Repair: £120-220
- 537i Repair: £150-250
- CDi Classic Repair: £90-160
- CDi Classic Regular Repair: £120-220
- CDi Highflow Repair: £120-220
- CDi RSF Repair: £150-250
- Greenstar 12i System Repair: £90-160
- Greenstar 2000 Repair: £120-220
- Greenstar 25 HE Combi Repair: £90-160
- Greenstar 25CDi Repair: £120-220
- Greenstar 25HE Repair: £90-160
- Greenstar 25i (ZWB 7-25) Repair: £120-220
- Greenstar 25Si Repair: £90-160
- Greenstar 27CDi Repair: £120-220
- Greenstar 28CDi Repair: £120-220
- Greenstar 30CDi Classic System ErP Repair: £100-£180
- Greenstar 30HE Repair: £90-160
- Greenstar 30i Repair: £90-160
- Greenstar 30si Repair: £120-220
- Greenstar 35 CDi Repair: £120-220
- Greenstar 42CDi Repair: £150-250
- Greenstar CDi Compact Repair: £90-160
- Greenstar Heatslave II Repair: £150-250
- Greenstar R29 40 HE Repair: £150-250
- Greenstar Ri Repair: £120-£190
- Greenstar Si Combi / i System Repair: £100-£180
- Greenstar System Repair: £120-220
- Greenstar ZWB7 Repair: £120-200
- Hideaway 90 Repair: £100-£180
- Highflow 440 CDi Repair: £150-250
- Highflow 550 CDi Repair: £150-250
- Highflow CDi Repair: £120-220
- R30 HE Plus Repair: £120-220
- Ri 25 HE Repair: £120-220
- Worcester 25/30 HE Repair: £90-160
- ZB 7 27 HE Repair: £120-200
- ZWB 7-25 Repair: £150-250
Source
Worcester Bosch E2 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
- Worcester Bosch 24/28/35 CDi MkII manual (PDF)
- Worcester Bosch 35 RSF manual (PDF)
- Worcester Bosch 532 / 537 / 542 manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026