Being trapped in summer or hot days, most people are able to get their house nice and cool. The most common method can be seen is people trapped themselves in their house and switch on air-conditioners as well as fans. But something important they do not take in account - fan and air-conditioner working out as one cooler.

The propellers of the fan tend to create a cone-shaped fast air region where usually one fan is enough for a medium size room. Somehow, a fan and an air-conditioner working together is a big nono. This is because the fast air in the region created by the fan keeps the “outside” air circling around the barrier, which how a wind curtain is formed.

Therefore, in this situation the existence of the air-conditioner is completely useless as the cold air cannot reach where it supposed to reach.