Worcester Bosch F7 Fault Code: Flame Still Detected
Hertfordshire, Bedfordshire & Cambridgeshire
F7 on a Worcester Bosch means the appliance has switched off but a flame is still being detected.
Same family as FA, and treated the same way. Turn it off and call an engineer rather than resetting it.
What F7 actually means
The boiler has ended its cycle and expects the flame signal to disappear. It has not.
That leaves two possibilities: a genuine flame when there should not be one, or a sensing circuit giving a false reading. The boiler cannot distinguish between them, so it locks out on the assumption that it might be the serious one.
What you can safely check yourself
Do not keep resetting it and do not leave it running.
Nothing. This is inside the appliance and it is Gas Safe work.
Turn the boiler off at the switch and ring an engineer.
When to stop, and why
Stop now. This is not a reset-and-see code.
What causes it beyond the simple checks
The service booklet starts with the electrode assembly, checking for dirt, wear, deposits and mechanical damage, because a contaminated or worn electrode will hold a false flame signal. Beyond that, moisture tracking on the electrode, a wiring fault in the flame sensing circuit, or a gas valve that is not shutting fully.
How Vantage can help
We are Gas Safe registered under 956889 and cover Hertfordshire, Bedfordshire and Cambridgeshire, with an emergency line answered 24 hours a day. Call us on 01462 506374. See also boiler repair and boiler servicing.
Frequently asked questions
What is the difference between F7 and FA?
They are closely related and both come down to the boiler detecting a flame when it should not. They are handled the same way: engineer, not reset.
Can I keep using the boiler?
No. Turn it off.
Will it be an expensive repair?
An electrode assembly is a modest part. A gas valve is more. You will get the price before any work starts.
Related fault codes
Other Worcester Bosch codes: FA · EA · F0 · all Worcester Bosch codes. The same fault on other makes: Vaillant F27. See also boiler repair.
In Worcester Bosch’s own words
The Greenstar CDi Classic engineer’s service booklet lists F7 as: Although appliance switches off, flame still detected.
Worcester Bosch use different code sets across their ranges and generations. The definition above is taken from the Greenstar CDi Classic service booklet. If your boiler is a different model and the code behaves differently, check the manual for your appliance or ring us and we will tell you what it means on your unit.
When to call an engineer
If the checks above have not cleared it, the next steps are engineer work and the boiler should not be reset repeatedly in the meantime. Call Vantage Plumbing and Heating on 01462 506374. We are Gas Safe registered under 956889, the line is answered by a person at any hour of any day, and you get a price before anyone starts.
Need help today?
Call and speak to a person, any hour, any day of the year. Get a fixed price quote or call 01462 506374.
Need help today?
Call and speak to a person, any hour, any day of the year, or get a fixed price quote online.
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Vantage Plumbing and Heating covers Hertfordshire, Bedfordshire and the surrounding areas. Call and talk to an engineer, or send us the details and we will come back to you with a price.
Gas Safe registered, number 956889. Emergency line answered 24/7.