EVAP-COND is a software package that contains NIST’s simulation models for a finned-tube evaporator and condenser. The “tube-by-tube” modeling scheme allows for specifying complex refrigerant circuits, modeling refrigerant distribution between these circuits, and accounting for non-uniform air distribution. Simulation results include local parameters for each tube such as inlet and outlet quality, temperature, enthalpy, entropy, pressure drop, mass flow rate for refrigerant and inlet and outlet temperature for air. Version 4.0 includes the option for optimization of refrigerant circuitry based on computational intelligence methods. EVAP-COND’s help menu provides information about the program’s capabilities and how to use it. The instructions include preparation of input data, execution of the program, and examination of simulation results. The graphical user interface contains several convenience features, including the ability to modify the existing refrigerant circuitry. EVAP-COND features: Tube-by-tube or tube sectional simulation One-dimensional, non-uniform air distribution Simulation of refrigerant distribution Refrigerant circuitry optimization Condenser model capable of simulating above the critical point REFPROP version 9.1 refrigerant properties 15 refrigerants and refrigerant mixtures: R22, R32, R116, R134a, R152a, R290, R404A, R407C, R410A, R507A, R600a, R717, R744, R1234yf and R1234ze(E)