BoilerFaultCodesYour boiler is struggling to monitor the temperature of the water moving through the system, which causes it to shut down for safety after running for a short time.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow and return sensor connection fault (may occur after several minutes of boiler operation.)
What causes this fault?
This fault occurs when the boiler's control board receives conflicting or missing data from the sensors that measure water temperature entering and leaving the unit. The most common reason is that one of these sensors has physically failed or the electrical wiring connecting them has become loose or damaged over time. Because the boiler cannot accurately track how hot the water is, it shuts down to prevent the system from overheating.
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 0A80 — 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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