High Lockout
04 on Vokera Linea 24

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

Insufficient water pressure in the system

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 reasons are a slow leak hidden somewhere in your pipework or radiators, or because you recently bled your radiators without topping the system back up.

This issue often appears when you turn your heating back on for the first time in autumn, as cooling pipes can contract and reveal small 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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