BoilerFaultCodesYour boiler has lost track of the system's water pressure because the internal sensor is failing or disconnected, causing the unit 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 fault
What causes this fault?
This fault occurs when the boiler's internal computer can no longer read the water pressure inside the system. The most common reason is that the pressure sensor has developed an electrical failure or has become blocked with sludge and debris, preventing it from sending a signal. Because the boiler cannot confirm there is enough water to operate safely, it shuts down to prevent the unit from 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 09 — no call-out fees, no surprises.
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