No Steam or Boiler Pressure
If your boiler pressure gauge on your Profitec Pro 800 is reading 0 bar, but you are able to get steam/hot water when you open the knobs, then your gauge is unreliable.
The same is true if your gauge indicates there is pressure inside the boiler when your machine has been off and cool for an extended period of time. If you determine your gauge is unreliable, it will need to be replaced. The instructions in the attachment below show how to replace the boiler pressure gauge on your machine.