BoilerFaultCodesYour boiler has stopped working because it cannot correctly measure the temperature of the water inside 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: Temperature sensor error.
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the temperature sensor, meaning it can no longer safely monitor how hot the water is. The most common reason is that the sensor has either worn out or suffered an electrical failure, but it can also be caused by loose or damaged wiring connecting the sensor to the main control board.
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 E74 — 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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