If you don’t put water (about 30mL) in the base you can expect the base to warp – that is why the Bacchi ships with the yellow paper ribbon threaded through between the base and the cylinder assembly to alert you to this
In fairness I think most owners do this
But a more subtle trap exists which we are publishing here (again) to ensure your Bacchi base has a long life
It is possible, if you are not wise to it, to not seat (or locate) the piston assembly on the base. While there is no chance of it happening once you have had it pointed out to you, if it were to occur the o-ring will be unable to form a seal and as the heat is applied to the Bacchi the water in the base will simply boil away until dry, the whistle won’t occur (as there will be no steam pressure to actuate it) and the base of the Bacchi will warp as a result of the extreme temperatures it will reach once no water is present to regulate it
My Bacchi is at the factory at the moment, otherwise I would take a video clip right now, but the point to note is that
after you have put about 30mL of water in the base, you then place the piston assembly on the base. Once you have done this, before you let go of the piston assembly rotate it right then left with a quick rotation of your wrist. This ensures that the piston assembly has seated on the base
You can check that the piston assembly has seated on the base by crouching down and checking with your eye that the bottom edge of the piston assembly is at a constant height off the base all the way around the circumference and isn’t sitting up at any point so that it is sitting at a slight angle on the base, rather than perpendicular.