Ventilating an indoor grown room is critical if you want the most profitable grow season possible. Ventilation systems not only keep the plants from reaching unsafe temperatures, but they also circulate air, which provides your plants with the much needed carbon dioxide they might otherwise use up in a stagnant environment. The right ventilation system will save you hundreds on lost product, and it can quickly pay for itself.
Grows rooms should never go above 95 degrees Fahrenheit. It is recommended that they be kept far lower, in the range of 75 to 85 degrees F. A proper ventilation system will make use of an extractor fan to pump warm air out of the grow room and an air pump that will refill the room with cool air. The amount of circulation you need will be based on the size of your grow room, the intensity of your lighting system, and the number of plants in the room.
Ventilation in and out of the room is vital, but something often overlooked in the process is the air movement inside the room. Oscillating fans should be used to keep the air moving in the room itself, so the cool air reaches each plant. Standard floor fans are ideal for this purpose.
Another important step in the ventilation process is CO2 injection. It's not only important that the air in your grow room stays at the right temperature, but it must also have the proper concentration of carbon dioxide. Too little carbon dioxide can be detrimental to plant growth. CO2 injection works by adding carbon dioxide to the ventilation system, perfectly simulating the ideal growth conditions.
A dehumidifier should be used in your grow room as well. Excessive moisture can ruin plants, and it could potentially harbor mold, mildew, and other undesirable issues. All these factors play a huge part on the overall yield of your grow room.