Maximum Yield USA December 2017 | Page 62

streamlining your ventilation system Air Conditioning One of the most common devices used in a modern indoor garden is an air conditioner. More specifically, a mini- split air conditioning system. These types of air condi- tioners are very efficient at removing excess heat and maintaining optimal temperatures and humidity condi- tions. Of all the devices used to control the atmospheric conditions in an indoor garden, an air conditioner gives growers the most control. There are many makes and models of air conditioners on the market, so it can be a little overwhelming for a new indoor horticulturist. When shopping for an air conditioner for an indoor garden, a grower needs to pay close attention to the machine’s BTU rating. British thermal unit (BTU) is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. Don’t let the definition of BTU confuse you. Instead, just think of BTUs as a way to quantify heating or cooling equipment. In other words, a grower can use a BTU rating to find the appropriate size air conditioner for his or her garden. Sizing Air Conditioning Equipment for an Indoor Garden The most “ common piece of equipment in any ventilation system is a motorized fan.” To adequately cool his or her indoor garden, a grower will need to consider the five major factors that influence the size of an air conditioner. Those factors are the dimensions of the growing area, the lighting equipment, the ballasts of the lighting equipment, the CO 2 equipment, and any remaining electrical accessories used in the garden. Room Dimensions When sizing an air conditioning system for an indoor garden, the first thing a grower should note is the size of the space that needs to be cooled. Although the heat created by the lighting system and other garden equip- ment will need to be considered to determine the required cooling load, the size of the space in cubic feet will deter- mine the minimum BTU requirements for the air condition- ing equipment. This minimum size can be determined by using a general BTU chart for room size. General BTU Chart for Room Size Cubic Feet BTUs 1 - 1,200......................................................... 5,000 1,200 - 1,600.................................................. 6,000 1,600 - 2,000.................................................. 7,000 2,000 - 2,400.................................................. 8,000 2,400 - 2,800.................................................. 10,000 2,800 - 3,200.................................................. 12,000 3,200 - 3,600.................................................. 14,000 3,600 - 4,000.................................................. 15,000 4,000 - 4,800.................................................. 18,000 4,800 - 5,600.................................................. 20,000 5,600 - 6,400.................................................. 22,000 6,400 - 7,200.................................................. 25,000 58 feature