Worcester Bosch · Greenstar CDi Compact ErP
E4 boiler fault code
Greenstar 28/32/36 CDi Compact ErP
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What E4 means
Preheat sensor on hot water inlet short or open circuit.
Gas Safe engineer: Note the code and contact a Gas Safe registered engineer for diagnosis.
If you smell gas, a CO alarm sounds, anyone feels unwell, or there is an unsafe flame, leave and call 0800 111 999 from outside.
Renting? Report it to your landlord or housing provider first. They are responsible for gas safety and boiler repairs, and the repair should not cost you.
Safe check
Note the displayed code. Do not open or adjust the boiler or repeatedly reset it; contact a Gas Safe registered engineer.
When to contact an engineer
Note the code and contact a Gas Safe registered engineer for diagnosis.
Source and provenance
- Greenstar CDi Compact ErP Installation, Commissioning and Servicing Instructions 6 720 813 276 (2015/07) · §8.5 Information and service menus, Status codes, printed pp.65–66; §8.6 Fault codes, Table 33 Locking fault and cause code listing, printed p.72
installation and service instructions
2015/07 · 6 720 813 276