How an indoor home grow setup works (3).

Equally important as the light cycle and temperature, is
ventilation. Therefore, like in a large greenhouse, you must
ensure constant air recirculation.

This can be rather laborious to do this in larger rooms,
however in a grow tent, you can do this efficiently using a simple extraction fan system. The extraction fan draws the warm, used air out of the upper section of the tent, and fresh air flows into the tent through the inlets in the lower section, where it immediately comes into contact with the plant.

Accordingly, you have some control over the temperature by changing the speed at which the air is extracted.
This means that, in most cases, you can avoid using additional climate control systems.