BoilerFaultCodesYour boiler is confused because it is looking for a hot water sensor that is either missing or has a broken connection, preventing it from heating your water correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Interrupt.: DHW outlet sensor on ext. contr. - UK link box is connected without the domestic hot water temperature sensor being bridged
What causes this fault?
This fault occurs when the boiler’s internal control system expects to see a hot water sensor connected but cannot find a signal. It is usually caused by a loose connection in the wiring link box or a faulty temperature sensor that has stopped communicating with the main circuit board. Without this data, the boiler shuts down as a safety precaution because it cannot accurately monitor the temperature of the water being sent to your taps.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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