BoilerFaultCodesYour boiler has lost connection with the sensor that measures the temperature outside, meaning it doesn't know how hard it needs to work to heat your home.
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: Short circuit of outdoor sensor S6.
What causes this fault?
This fault occurs when the electrical signal from the sensor located on your outside wall is interrupted or crossed. The most common reasons are water getting into the sensor casing or the external wiring being damaged by garden maintenance or pests. Because the connection is broken, the boiler loses its ability to adjust its power based on the outdoor weather.
This fault is more common during autumn and winter when heavy rain or freezing conditions can enter the sensor housing and cause an electrical short.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F027 — no call-out fees, no surprises.
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