BoilerFaultCodesYour boiler has detected a fault with its internal temperature sensor, preventing it from heating your water and radiators safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: primary NTC open/short circuit
What causes this fault?
This fault occurs when the boiler's main temperature sensor, which monitors the heat of the water inside the unit, fails or loses connection. The most common reason is that the internal component has simply worn out over time or a wire has come loose, meaning the boiler can no longer safely regulate its own temperature.
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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