BoilerFaultCodesTechnical description
Communication fault between Master and Slave boards
What causes this fault?
This fault occurs when the boiler's internal safety circuit is broken, usually because the system has lost too much water pressure to operate safely. It can also be triggered if the unit begins to overheat, causing a safety sensor to trip and shut down the burner to prevent damage. The most common reasons are a leak somewhere in the central heating system or a faulty sensor that is incorrectly reporting a problem.
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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