BoilerFaultCodesTechnical description
DHW mode – burner error
What causes this fault?
This fault happens when the boiler successfully starts but cannot maintain a steady flame while heating your water, causing the system to shut down for safety. It is typically caused by a malfunctioning gas valve that isn't providing the right fuel mix or worn-out ignition parts that can no longer sense the flame correctly. In some cases, a damaged seal around the burner can also disrupt the combustion process and trigger this error.
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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