BoilerFaultCodesYour boiler is struggling to read how much water is in the system because of a sensor issue, which has caused it to stop working for your 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 in the wrong range (too low)
What causes this fault?
This fault occurs when the boiler's internal computer receives an electrical signal from the water pressure sensor that is outside its expected range. The most common reason is a build-up of sludge or debris blocking the sensor's opening, though it can also be caused by the sensor's internal electronics failing or a loose connection in the wiring.
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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