High
50° neon flashing on Potterton Performa 24

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

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.

What the manual says

Manufacturer manual

The water pressure is less than 0.5 bar. Check the water pressure and top up the system

From this model's manual
Verified against the Performa 28i installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the internal sensors detect that there isn't enough water volume to safely transfer heat around your home. The most common reason is a slow leak in the radiator network or pipework, but it can also happen if you recently bled your radiators without topping up the pressure afterwards.

This issue often surfaces when you turn the heating back on for autumn, as the system settles after being dormant or develops leaks from expanding and contracting metal.

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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