BoilerFaultCodesYour boiler has detected that its flow and return sensors are providing conflicting readings, which prevents it from heating your home safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Deviation in the water pressure sensor/return temperature sensor
What causes this fault?
This fault occurs when the boiler detects a permanent difference between the temperature readings on the flow and return pipes. It usually happens because one of the internal sensors has failed, or because there is a physical blockage or pump issue preventing water from circulating evenly through the system.
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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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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