BoilerFaultCodesYour boiler has lost connection with the sensor that monitors water returning from your radiators, meaning it cannot safely regulate its temperature.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return probe with contact open
What causes this fault?
This fault occurs when the boiler's control board stops receiving a signal from the sensor that monitors the temperature of the water coming back from your heating system. The most common cause is a failed internal sensor or a loose wire connection, which prevents the boiler from knowing if the system is overheating.
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 E45 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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