BoilerFaultCodesTechnical description
The diagnostics will indicate the nature of the fault to assist a speedy and effective repair
What causes this fault?
This fault occurs when the communication link between your boiler and the external sensor is broken or sending illogical data. The most common reasons are moisture getting into the sensor casing, corroded electrical connections, or the thin wiring being accidentally damaged by garden maintenance or pests.
This fault is more common following periods of heavy rain or snow, which can cause moisture to penetrate the sensor housing and short-circuit the sensitive electronics.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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