BoilerFaultCodesYour boiler has detected an electrical fault with the internal sensor that monitors the temperature of its hot water storage tank.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Short-circuit on heat retention storage tank sensor: Sensor plug has mass short to the casing, short-circuit in wiring loom, sensor faulty
What causes this fault?
This fault occurs when the boiler's control board receives a scrambled or impossible electrical signal from the sensor that monitors your hot water storage. The most common reason is that the sensor has failed internally or the protective coating on the wiring has worn through, causing an electrical 'short' against the metal casing. It can also be caused by water or moisture getting into the electrical plug, which disrupts the connection.
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 F.13 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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