BoilerFaultCodesYour boiler has lost connection with its outside temperature sensor, which means the heating might not adjust correctly to the weather.
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: Outdoor sensor short / Outdoor sensor open
What causes this fault?
This fault occurs when the electrical signal between the boiler and the external sensor is broken or distorted. The most common reason is water ingress or corrosion inside the sensor housing on the outside wall, or damage to the cable caused by gardening accidents or pests.
This fault is more common during autumn and winter when heavy rain or freezing temperatures can expose weaknesses in the sensor's weatherproofing.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like OUTDR — no call-out fees, no surprises.
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