BoilerFaultCodesYour boiler has sensed that its two main temperature sensors aren't agreeing with each other, so it has shut down to prevent potential overheating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow/return temperature sensor difference (permanent)
What causes this fault?
This fault occurs when the boiler's internal computer compares the readings from the flow and return pipes and finds they are too far apart or inconsistent. The most common reason is that one of these sensors has become faulty or uncalibrated, causing it to send an incorrect temperature reading to the main control board. In some cases, it can also be caused by a communication issue in the wiring that connects these sensors to the brain of the boiler.
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 F.72 — 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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