Vaillant · Turbomax Plus Boilers
This fault code indicates that the Ecomax Pro 828E boiler has detected a critically low water level or pressure within your heating system.
Click steps to track your progress.
Check your boiler's pressure gauge; if it's too low (e.g., below 1 bar), repressurize the system according to your boiler's manual.
Look for any signs of water leaks in your heating system or around the boiler.
Restart the boiler after ensuring adequate pressure.
If the problem persists or pressure drops quickly, contact a qualified heating engineer to find and fix any leaks.