BoilerFaultCodesYour boiler has stopped working because it cannot accurately measure the temperature of the water leaving the unit to heat your home.
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
What causes this fault?
This fault occurs when the boiler's main control board loses communication with the sensor that monitors the temperature of the water heading to your radiators. The most common reason is that the internal sensor has developed a physical defect or the electrical wiring connecting it to the brain of the boiler 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
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F.00 — 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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