BoilerFaultCodesTechnical description
A fault on the hot water or central heating temperature sensor is indicated.
What causes this fault?
This fault occurs when the sensors that monitor water temperature fail to send a clear signal to the boiler’s main control board. The most common reason is that the internal components of the sensor have degraded over time or developed a lime-scale coating, preventing them from providing an accurate reading. In some cases, the electrical wiring connecting these sensors has become loose or damaged, leading to an instant safety shutdown.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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