Abstract: A Heat and mass transfer model between air and water of fan coil unit is introduced in detail and is solved by concept of equivalent dry running condition, which transforms wet running condition to dry running condition to simplify the calculating process by excluding the dehumidifying coefficient. With a stationary distributed parameter model, analysis on running characteristics under steady condition, especially on performance versus various geometry parameters is made, which builds a base for optimization of fan-coil units designing.

Key words: Fan coil unit, Steady model, Various geometry parameters