Room too hot

I have eight 1,000-watt lights in a 200 square foot room. When they are on, the room reaches 90-100?F (32-38?C). Two tubes, six inches and eight inches in diameter, supply fresh air to the room, and a 12-inch tube is used for exhaust. A small window air conditioner also cools the room. With four lights on, the maximum temperature is 76?F (24.5?C).
I am weighing my options, including air-cooled reflectors. What do you think I should do?


When you run four lights, the maximum temperature is 76?F (24?C). Running an additional four lights pushes the temperature up to 100?F (37?C). Each light produces about 3,200 BTU’s of heat, so the problem is that the room is producing an extra 12,800 BTU’s that are not being cooled or ventilated out.

Air-cooled lights may be the answer to the problem. They seal the heat that the lights produce within the reflectors and then ventilate it out using tubing and blowers. These reflectors stop at least half of the heat being produced from reaching the garden.

Another solution is to increase the capacity of the intake and outtake tubes by installing more powerful blowers on either end. The six-inch tube has an area of 28 inches, the eight-inch has an area of 50 inches. The 12-inch exhaust tube has an area of about 113 inches. Installing wider intake tubes would increase their capacity to carry cool air into the room. This would also help kept the space cool.

A larger air conditioner, rated at 12,000 BTU’s more than the one you are using would also lower the temperature to an acceptable level.

I would try a combination of solutions. The most economical would be to install air-cooled reflectors, install new tubes with larger diameters and more powerful blowers. These improvements will keep the space in the low 70’s?F (low 20’s?C), a comfortable temperature for your plants.

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