How can I simulate a model that doesnt use HVAC system, it is only refrigerated by a normal electric plugable fan and natural ventilation. I've read others question regarding this topic, but they all said that in OS 1.9 it would probably be resolved. Now the OP 1.10 is already developed. In my model, in "thermal zones" I add to each Natural Ventilation in Zone Equipment, but it gives me errors, also tried to add unit ventilator cooling and gives me error. What can I do?