High Lockout
F1 on Ideal Logic Max System

Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely.

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 fire up safely. The most common reason is a small leak somewhere in your central heating pipework or radiators, though it can also happen if you have recently bled your radiators and haven't topped the pressure back up.

This fault is frequently seen in autumn when homeowners turn their heating back on for the first time or bleed their radiators to remove air pockets.

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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