BoilerFaultCodesYour boiler has lost communication with the water pressure sensor, meaning it cannot confirm if there is enough water to run safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No water pressure signal recievced fom MMI
What causes this fault?
This fault occurs when the boiler's main control board loses the electrical signal from the water pressure sensor. The most common reason is a loose or damaged wiring connection between the internal components, though it can also be caused by the sensor itself failing electronically. Because the boiler can no longer verify that there is enough water to operate safely, it will shut 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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