Technical description
insufficient water pressure in the heating system
What causes this fault?
This fault occurs when the water level inside your central heating system drops below the minimum level required to operate. The most common reason is a slow leak from a radiator valve or pipework, though it can also happen if you have recently bled your radiators and haven't topped the pressure back up.
This issue is more frequent in autumn when homeowners turn their heating back on for the first time or bleed their radiators to prepare for winter.
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.