BoilerFaultCodesYour boiler has lost the ability to monitor its own water pressure due to a sensor or wiring fault, causing the system to shut down 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: Water pressure sensor signal out of range (too low) | Cable to water pressure sensor is broken or has a short-circuit at 0 V or water pressure sensor defective
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the component that measures water pressure. The most common reason is a failed digital sensor that has worn out internally or a break in the thin wires connecting that sensor to the main control board. Because the boiler can no longer verify if there is enough water to operate safely, it shuts down to prevent overheating.
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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