Technical description
System water pressure low
What causes this fault?
This fault occurs when the water pressure inside your heating system drops below the minimum level required for the boiler to operate safely. The most common reasons are a slow leak from a pipe or radiator valve, or air being bled from the radiators without the system being topped back up with water.
This fault is frequently seen in autumn when homeowners turn their heating back on for the first time and find the pressure has gradually depleted over the summer months.
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.