BoilerFaultCodesWhat the manual says
Manufacturer manualNo flame during start-up.
What causes this fault?
This fault occurs when the boiler's control system attempts to start the combustion process but cannot detect a stable flame. The most common reasons are a lack of gas supply to the unit, a worn-out ignition spark, or a build-up of carbon on the internal probes that monitor the fire. Without a confirmed flame, the boiler stops for safety reasons to prevent unburnt gas from entering the system.
This fault can occur more frequently during the first cold snap of autumn when internal components that have been dormant all summer are suddenly required to work under high load.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Avoid the next call-out bill
A cover plan would handle faults like F004: no call-out fees, no surprise bills.
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