Ideal boiler displays F9 and shuts down, may occur intermittently
Safety Warning
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
How to Fix / Troubleshooting
Safety first: Turn off the boiler at the fused spur before any inspection. Do not remove the sealed combustion case.
User checks:
- Power cycle: Turn off the boiler for 5–10 minutes, then turn back on and reset. Sometimes transient faults clear.
- Check for water leaks: Look under and around the boiler for signs of water. If you see water near the electronics, turn the boiler off and call an engineer.
- Surge protection: If your property has frequent power surges, consider having an electrician install surge protection.
Engineer actions: Inspect PCB for burn marks or corrosion, check all connectors, rectify any leaks from components such as the automatic air vent or pump, and replace the PCB if confirmed faulty.
Repair Difficulty
Required Part
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