Dears Srs.,

I am simulation a service building with cooling loads, about 4000W/m2 with a
schedule 100% activates in all hours. My system is an air handling unit with
return and free cooling. The air handling unit has a cooling coil, a heating
coil and a direct evaporation cooling coil 100% activated. The system has
humidification and the minimum room relative humidity is 30%. The
temperatures of insufflation are 14-20 ?C for cooling and 20-31 for heating.
The room set point is 18-27 ?C.

When I run the simulation, in winter the cooling consumption is 0 because
the operation of free cooling. On the other hand, in Winter I have
consumption of humidification to control the humidity to 30 %. However the
direct evaporative cooling coil does not work as I expected because the
direct evaporative cooling coil should help in humidification of the rooms.
My question is: Why the direct evaporative cooling coil does not work in
winter, when I have height consumption of humidification. In practice the
direct evaporative coil work all the year.

The Best Regards,

Ricardo