BoilerFaultCodesWorcester Bosch 2 pulses Fault Code
Also written as 2PULSES — same fault.
The Worcester Bosch 2 pulses fault code means: your boiler has been left in a manual testing mode after a service or inspection and needs to be switched back to its normal operating setting.. It appears on 13 Worcester Bosch models in our database.
Technical description: Service mode switch in min position.
What causes the Worcester Bosch 2 pulses fault?
This issue occurs when a technician accidentally leaves a physical switch on the internal control board set to 'minimum' after performing a service or safety check. Because the boiler is being told to stay at its lowest power setting for testing purposes, it cannot respond to your thermostat's request for full heat. It is a simple human error where a manual override was not deactivated before the boiler casing was put back on.
DIY fix possible
Locate the service mode switch (or dial) on the boiler control panel.Ensure the switch is moved from the 'Min' or 'Service' position back to the 'Normal' or 'Off' position.Perform a simple reset by pressing the reset button to clear the flashing light.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Worcester Bosch models that show the 2 pulses fault code
Click a model for the full fault code list and model-specific repair notes.
- 24 RSF Repair: £0-80
- 26 CDi Xtra Repair: £0-80
- 30i Junior Repair: £0-80
- 35 RSF Repair: £0-80
- Danesmoor Repair: £0-90
- Greenstar 12i System
- Greenstar 12Ri Repair: £0-80
- Greenstar i Junior
- Greenstar Ri Repair: £0-80
- Heatslave Repair: £0-80
- Hideaway Repair: £0-80
- Junior 24i Repair: £0-80
- Junior 28i Repair: £0-80
Source
Worcester Bosch 2 pulses fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026