Boiler shows F05; often associated with pump or circulation problems on some Ferroli models.

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Seized pump, Blocked system or filter, Airlock in pump, Faulty pump wiring or PCB output

Safety first: Turn off power and allow the boiler to cool before touching the pump or pipework.

Check pressure and bleed: Ensure system pressure is correct and bleed radiators to remove air.
Engineer checks:
- Verify pump is receiving power and is spinning freely.
- Manually free a stuck pump rotor if possible, or replace the pump.
- Clean any system filter (e.g., magnetic filter) and check for sludge.
- Check PCB pump relay/output if pump is good but not powered.

Hard 4/5

Primary Circulation Pump

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