BoilerFaultCodesYour boiler's internal sensor that monitors water pressure has lost electrical contact or has failed, causing the system to stop working for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Signal water pressure sensor in the wrong range (too low): Line to water pressure sensor is interrupted or has a short-circuit to 0V or water pressure sensor faulty
What causes this fault?
This fault occurs when the boiler's control board loses the electronic signal from the sensor that monitors internal water pressure. The most common reason is that the sensor itself has developed an internal electrical fault or the wiring connecting it to the main computer has become loose or damaged. Without this data, the boiler shuts down to prevent itself from firing while potentially dry.
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.73 — 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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