Hello I am a engineer based in India. Please help me in a designing Soda Cart. I have kept the traditional design aside. All the machines in market have builtin Carbonator and iceplate. Some have Icebin, other use a compressor to achieve to the job. I want to get away from this design since it's bulky and require a good power source (All compressor based machines consume >800W).

The soda cart that I have thought about will have a 40L Stainless Steel/PVC container in which water will be filled at filling unit at 80PSI together with C02. This container will then be loaded onto the cart together with Syrup Canister. [IMG][/IMG]waterspigot_88783.jpg

Long time since I touched Fluid Mechanics:
Q1: How will the pressure inside Soda Cylinder vary as water is taken out? I think water is quite compressible so leaving the vapour pressure of CO2, pretty much the pressure change will be sudden.