BoilerFaultCodesWorcester Bosch 2948 Fault Code
The Worcester Bosch 2948 fault code means: your boiler is struggling to stay lit when it is running at its lowest power level, often causing it to shut down for safety.. It appears on 5 Worcester Bosch models in our database.
Technical description: No flame signal with low output
What causes the Worcester Bosch 2948 fault?
This fault occurs when the boiler's internal sensor can no longer detect a steady flame while the unit is operating at its quietest, most efficient setting. The most common reason is that the sensing probe has become dirty or worn out, though it can also be caused by the gas valve failing to deliver a consistent flow of fuel at low pressures.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Worcester Bosch models that show the 2948 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch 2948 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 Greenstar 1000 manual (PDF)
- Worcester Bosch Greenstar 2000 manual (PDF)
- Worcester Bosch Greenstar 27CDi manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026