BoilerFaultCodesTechnical description
Constant temperature control units
What causes this fault?
This fault occurs when the electrical signal from the hot water sensor becomes constant, usually because the internal wiring of the sensor has failed or become damaged. This prevents the boiler from knowing the temperature of the water in your cylinder, causing it to stop heating your taps to prevent overheating. The most common reason is a component failure within the probe itself or water ingress affecting the electrical connections.
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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