BoilerFaultCodesWhat the manual says
Manufacturer manualFlame loss during operation
What causes this fault?
This fault occurs when the boiler successfully lights but cannot maintain a steady flame, causing the system to shut down for safety. The most common reasons include a blockage in the condensate drainage pipe, an unstable gas supply, or a buildup of carbon on the electrodes that monitor the flame.
This fault is significantly more common during freezing winter temperatures, as the external condensate drainage pipe can freeze and cause water to back up into the boiler.
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 52 fault codes on the Flexicom hx
Seeing a different code? Every code this model can display, in one place.