BoilerFaultCodesWhat the manual says
Manufacturer manualStart-up failure: Ignit. unsuccessful - Failure during start-up or ignition unsuccessful. Gas pressure monitor or thermal cut-out has been triggered.
What causes this fault?
This fault occurs when the boiler attempts to ignite three times but fails to establish a steady flame. The most common reasons include an interrupted gas supply, a worn-out ignition spark plug, or a component failure that prevents the gas valve from opening correctly.
This fault is more frequent during extreme cold snaps, as external gas meters or regulators can sometimes freeze, restricting the flow of gas to the property.
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 F.28: no call-out fees, no surprise bills.
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