dominico wrote:It looks like you posted the same video twice.
My guess is that your inlet valve is set almost closed.
That nut hanging down behind the group covers a valve which allows you to adjust the flow. The valve is very finicky, only a half turn between fully closed and fully open.
Here is a video I made to demonstrate how the valve works: As you can see the far group has the nut still in place, with the near group I have removed it to be able to adjust the valve.