Sometimes the last thing you want is to come home and find your Ideal boiler is showing you a fault code on the front display. Never fear help is on hand, here’s my simple explanation of what F fault codes mean to get your Ideal boiler up and running again:
F fault codes
FD: No water flow
Usually due to an installation fault within air locks, pump or wiring
- Try repressurising your boiler
- If that doesn’t help, call your installer
F1: Low water pressure
- Top up your boiler’s water pressure to 1.5 using the in-built in filling loop
- If you’re still facing issues, contact a Gas Safe registered engineer
F2: Flame loss
- Typically occurs with older boilers and low-efficiency systems
- Check other gas appliances
- Reset your boiler
- Consider getting a new boiler installed
F3: Fault with fan
Can be caused by damaged connections, air pressure switch or circuit board.
- Call a Gas Safe registered engineer
F4: Thermistor fault
This could be a problem with your boiler’s flow thermistor or circulation issues.
- Call a Gas Safe registered engineer
F5: Return thermistor fault
Tends to be a faulty NTC (Negative Temperature Coefficient) return thermistor, a damaged connection, or a faulty printed circuit board.
- Call a Gas Safe registered engineer
F6: Outside sensor fault
Can be caused by a recent weather compensator installation.
- If a weather compensator wasn’t installed recently, or you don’t have one at all, call a qualified engineer
F7: Low mains voltage
Not a boiler fault.
- Check your property’s mains electricity
- Contact your installer
F9: Printed circuit board (PCB) fault
Repairing this fault could be costly.
- It may be worth considering getting a brand new boiler installed
Prepare for the best this winter and let one of our home experts or me handle your repair needs, to get things working again in no time.
Ideal boiler problems: fault codes Boiler installation