BoilerFaultCodesTechnical description
Safety shutdown and/or internal fault
What causes this fault?
This fault occurs when the boiler's control system detects a critical safety issue, most often failing to light the flame after several attempts. It can be caused by a lack of gas reaching the burner, a worn-out spark electrode, or an electrical failure within the main control board. Essentially, the boiler has stopped working to prevent unburnt gas from building up or to protect its internal components from damage.
This issue often surfaces during the first cold snap of autumn when the boiler is pushed to work harder after being idle throughout the summer.
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.
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