BoilerFaultCodesYour boiler has stopped working because one of its internal temperature sensors has developed an electrical fault and is reporting incorrect information.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Outlet probe short-circuited
What causes this fault?
This fault occurs when the electrical sensor that measures the water temperature exiting the boiler fails or loses its connection. Over time, heat exposure or moisture can cause the sensor's internal wiring to break down or short-circuit, preventing the boiler from knowing if it is safe to continue heating.
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 E42 — 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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