BoilerFaultCodesYour boiler has stopped working because a sensor that monitors the temperature of the water returning to the unit has likely failed.
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 error – could be damanged
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor that monitors water temperature coming back from your radiators. The most common reason is that the internal components of the sensor have degraded over time or the electrical connection has become unstable, preventing the boiler from operating safely.
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 112 — 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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