BoilerFaultCodesYour boiler's hot water storage tank sensor has developed a fault and can no longer accurately read the water temperature.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: TEMPERATURE ON STORAGE VESSEL: CIRCUITS OPEN OR SHORT CIRCUIT. CHECK RESISTANCE OF THE THERMISTOR.
What causes this fault?
This fault happens when the electronic sensor responsible for monitoring the temperature inside the hot water storage tank fails or loses its connection to the main control board. The most common reason is the internal degradation of the thermistor's electrical resistance over time, or moisture causing a short circuit in the wiring harness.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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