The best approach to cooling a hot room depends on the external environment and the specific conditions of the room in question. Here are two scenarios to consider:
Blowing air into a hot room: If the external temperature is cooler than the indoor temperature and there is a source of cool air, blowing air into the room can help create positive pressure. This positive pressure can force the hot air out of the room through any gaps or openings, thus promoting better ventilation and cooling. This method is effective when the outside air is cooler, such as during the evening or at night.
Blowing air out of a hot room: If the external temperature is significantly hotter than the indoor temperature, and there is no access to cooler air, blowing air out of the room can help remove the hot air from inside. This method can create a negative pressure inside the room, which can cause air to be drawn in from outside through gaps and openings. While this may not immediately cool the room, it can prevent the room from becoming even hotter and can be useful during the day when the outside temperature is scorching.
In both cases, it's essential to consider the overall airflow and ventilation system in the room. For the best cooling results, you may also want to use fans or air conditioners to circulate the air and help maintain a comfortable temperature.
Ultimately, the effectiveness of either approach will depend on various factors, including the outside temperature, indoor humidity, insulation of the room, and the efficiency of the cooling equipment used. For long-term and effective cooling, using an air conditioner or a combination of cooling methods may be the most efficient option.