BoilerFaultCodesYour boiler is unable to heat your hot water because a sensor that monitors the temperature of the water cylinder has stopped communicating with the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No DHW heating - Cylinder temperature sensor 2/outlet sensor lead break
What causes this fault?
This fault occurs when the boiler loses its connection to the sensor responsible for monitoring the hot water storage temperature. The most common reason is a physical failure of the internal sensor probe or damage to the wiring harness, causing an electrical 'break' that prevents the control board from receiving data.
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 59 — no call-out fees, no surprises.
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