A1
Pump stuck or running in air
The boiler has detected a circulation-pump condition consistent with a stuck pump or pump operation with insufficient water.
What this code means
The boiler has detected a circulation-pump condition consistent with a stuck pump or pump operation with insufficient water.
Possible causes
- Pump stuck
- Air in system
- Low water content or circulation issue
- Pump fault
Common symptoms
- A1 displayed
- Heating circulation may stop
- Boiler may lock out
Checks to make
- Check system pressure from the user controls
- Do not dismantle the pump
- Arrange heating-engineer diagnosis if the code remains
Safety
- Do not remove the boiler casing or work on internal pump components unless appropriately qualified.
Model notes
Worcester technical literature describes A1 as pump stuck or running in air.