Technical description
Without flue gas cascade
What causes this fault?
This fault occurs when the boiler's internal computer has been told to look for other boilers to work alongside, but it cannot find any connected. It is usually triggered by an incorrect setting during a software update or if the wrong configuration code was entered when the main circuit board was replaced. Essentially, the boiler is waiting for communication from a 'team' of units that does not exist.
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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