High Lockout
F1 on Ideal Logic Combi C24 C30 C35

Your boiler has detected that the water pressure inside the system is too low to run safely and has stopped working as a result.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Low Water Pressure

What causes this fault?

This fault occurs when the internal water pressure drops below the minimum level required for the boiler to operate safely. The most common reasons are a slow leak from a radiator valve or pipework, or a loss of air pressure in the expansion vessel which helps regulate the water volume.

This fault is frequently seen in autumn when the heating is first turned on after summer, as thermal expansion can highlight existing slow leaks or pressure drops.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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