BoilerFaultCodesYour boiler has stopped working because it cannot accurately measure the temperature of the water coming back from your radiators.
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 Sensor failed open or closed circuit Replace sensor
What causes this fault?
This fault occurs when the internal computer can no longer read the electrical signal from the sensor that monitors cool water returning to the boiler. It is usually caused by the sensor's internal components failing due to age or a loose connection in the wiring harness. When the boiler loses this vital temperature data, it shuts down as a safety precaution to prevent 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 6 — no call-out fees, no surprises.
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Potterton Envoy is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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