BoilerFaultCodesYour boiler has detected that a key internal thermometer is broken or disconnected, meaning it cannot safely monitor the temperature of the water leaving the unit.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Temp.sensor fault: Flow temperature sensor defective or not connected.
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor that measures the heat of the water being sent to your radiators. The most common reason is that the internal sensor has physically failed due to age or heat stress, though it can also be caused by loose wiring or dampness affecting the electrical connections.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like 3 6. — no call-out fees, no surprises.
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Remeha W40 60 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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