BoilerFaultCodesWhat the manual says
Manufacturer manualLoss of flame during operation fault
What causes this fault?
This fault occurs when the boiler successfully starts but cannot maintain a steady flame, causing it to shut down for safety. The most common reasons are a temporary interruption in the gas supply, a dirty flame sensor that can no longer 'see' the fire, or a buildup of debris in the burner area.
This fault is more common in winter, as a frozen external condensate pipe can cause water to back up into the boiler and extinguish the flame.
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 F29: no call-out fees, no surprise bills.
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Related fault codes
All 70 fault codes on the Ultracom 35 Store
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