BoilerFaultCodesYour boiler has shut down because it keeps losing water pressure and likely has a leak somewhere in the heating system or the unit itself.
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 lost 4 times in 24 hours – possible leak, check system and boiler
What causes this fault?
This fault occurs because the boiler has detected a significant and repetitive drop in water pressure, forcing it to shut down to prevent internal damage. It is usually caused by a physical leak within your radiators, pipework, or the boiler's internal components, such as a failing pressure relief valve. If the system cannot maintain a steady pressure four times within a single day, the software triggers this safety lock to alert you to the underlying leak.
This fault is frequently seen in autumn when the heating is turned back on after summer, as the change in temperature and pressure can cause weakened seals or joints to start leaking.
DIY fix possible
Check for visible water leaks under the boiler and around your radiators or valves.Top up the system pressure to 1.5 bar using the external filling loop.Reset the boiler and monitor if the pressure drops again.
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