Abstract: A housing has a vertical separation wall. The vertical separation wall forms a filling chamber on one side. The housing has a horizontal separation wall on the other side. The horizontal separation wall forms a cooling chamber. A quantity of a liquid in the filling chamber has an apertured horizontal plate at about the middle elevation of the filling chamber. A smaller end-user tank is provided on the plate. The level of liquid is sufficient to immerse the lower portion of a smaller end-user tank. An air conditioning system includes a compressor unit located in the cooling chamber. The air conditioning system includes a refrigerant coil in the filling chamber beneath the plate. A large supply tank of gas is laterally displaced from the housing. A supply tube connects the large supply tank with the smaller end-user tank within the housing.