BoilerFaultCodesYour boiler's outside temperature sensor is either giving an incorrect reading or has lost communication with the main control system.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Outside temperature with weather compensator – Vaillant controller only
What causes this fault?
This fault occurs when the boiler loses contact with the sensor located on the outside of your property, which is responsible for monitoring the outdoor temperature. The most common reasons are a break in the communication cable due to weather damage or a internal component failure within the sensor itself. Without this data, the boiler cannot automatically adjust its efficiency based on the weather conditions outside.
This fault is often noticed during the transition into autumn or winter when the heating system's weather compensation features are first called upon after the summer break.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like D.47 — no call-out fees, no surprises.
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