BoilerFaultCodesYour boiler has stopped working because a internal sensor that monitors the temperature of the water returning to the unit has developed an electrical fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return sensor short circuit
What causes this fault?
This fault occurs when the boiler's internal computer detects a broken electrical signal from the sensor that monitors cooled water returning to the unit. The most common reason is that the sensor's internal components have failed or the wiring connecting it to the main control board has become damaged or loose.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 0A43 — 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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