BoilerFaultCodesYour boiler has lost connection with the sensor that monitors the outdoor temperature, making it difficult for the system to adjust its heat settings efficiently.
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 Sensor Fault
What causes this fault?
This fault occurs when the boiler's main control board can no longer communicate with the external sensor mounted on the outside of your home. The most common reason is damage to the thin communication wires by pests or garden maintenance, or water entering the sensor housing and causing corrosion. Because the boiler no longer knows how cold it is outside, it cannot automatically adjust its temperature to save you money on your energy bills.
This fault is often noticed during autumn or the first cold snap, as this is when the boiler starts relying on the outdoor sensor to ramp up the heating demand.
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 F6 — no call-out fees, no surprises.
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