BoilerFaultCodesTechnical description
Heat exchanger temp sensor disconnected
What causes this fault?
This fault occurs when the boiler's internal computer loses track of the heat exchanger's temperature, usually because the connection to the sensor has broken or the sensor itself has failed. Over time, the constant heating and cooling of the boiler can cause the wiring to become brittle or the sensor to degrade, preventing it from sending a clear signal. Without this safety information, the boiler shuts down immediately to prevent the unit from overheating.
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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