BoilerFaultCodesYour boiler's internal sensor is struggling to accurately read the water pressure, which prevents the system from operating safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: System pressure sensor fault
What causes this fault?
This fault occurs when the electronic sensor responsible for monitoring the water level inside the boiler fails or provides an illogical reading. The most common reason is that the sensor's internal diaphragm has become blocked with system sludge or the electrical connections have corroded over time. Because the boiler cannot confirm there is enough water to operate safely, it shuts down to prevent internal 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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