BoilerFaultCodesYour boiler has stopped working because one of its internal temperature sensors is reading an unusually high or low temperature, causing the system to shut down for protection.
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 out of range.Sensor measures a temperature outside normal working range
What causes this fault?
This fault occurs when the sensor responsible for monitoring the water returning to the boiler sends a signal that is outside of its expected safety limits. The most common reason is that the sensor has developed an internal electrical fault or the wiring connecting it to the main control board has become damaged. In some cases, it can also be triggered if the water inside the system reaches an extreme temperature that the sensor is unable to process.
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 0A44 — 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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