BoilerFaultCodesYour boiler has stopped working because it cannot correctly measure the temperature of the water leaving the unit due to a faulty internal sensor or wiring.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow temperature sensor short-circuited. Sensor not or badly connected, bad connection or sensor fault.
What causes this fault?
This fault occurs when the boiler's control board receives an impossible electrical signal from the sensor that monitors the hot water leaving the unit. The most common reason is that the internal sensor has suffered an electrical short-circuit or the delicate wiring connecting it to the main computer has become loose or damaged.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E.04 – .01 — 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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