BoilerFaultCodesYour boiler's outdoor temperature sensor is reporting an error, which may prevent your heating from working efficiently or starting up at all.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: External probe fault sensor damaged or short circuited – check the wiring
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor located on the outside of your home. The most common reason is that moisture or corrosion has damaged the external sensor's casing, or the thin electrical wiring connecting it to the boiler has been cut or degraded by the weather.
This fault is more common during autumn and winter when heavy rain or freezing temperatures can cause moisture ingress into the external sensor housing.
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 F37 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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