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dehumidifier cannabis grow room

Dehumidifier cannabis grow room

There are many humidity control options on the market. Most of which are designed for traditional purposes, such as industrial processes and storage. These dehumidifiers are optimized for different settings, making their operation sub-optimal in the specific conditions found in cannabis grow rooms.

All DG units are equipped with a patent protected air circulation system that ensures uniform climate conditions throughout the space.

Cannabis is extremely sensitive to humidity. It’s susceptible to a variety of humidity related diseases such as botrytis, downy mildew and alternaria. Treating humidity in the growing space with a dehumidifier for cannabis is the most efficient method to eliminate diseases.

Due to cannabis’ strict regulations, both for medicinal and commercial use, it’s necessary to eliminate disease without chemicals. In order to achieve this, growing spaces require dehumidification.

Oregon based cannabis grower, Elad, has been using DryGair dehumidifiers for several years.

Do You Need a Dehumidifier for Cannabis Cultivation?

While many growers attempt to reduce humidity with the use of fans or cooling systems, such as HVAC, these methods fail to achieve the highest efficiency. This is due to these systems reducing humidity as a byproduct of their operation, rather than a dedicated, optimized condensation system.

The GrowAire™ solutions unit uses a full-size hot gas reheat system that uses energy absorbed through the evaporator coil. The evaporator coil gains this energy once the overall temperature has been dropped to remove excess moisture in the grow facility. This energy is not new energy, rather energy already paid for and created by the facility. This energy recycling process negates the need for any type of new energy to be created to reheat the cannabis plants within the grow facility.

We support GrowAire™ solutions to provide indoor cannabis grow rooms, drying rooms and cannabis farming facilities with the necessary components to successfully protect crops and allow for enhanced growth within the most controlled environments.

Desert Aire has been partnering with cannabis growers to educate and transform indoor environments into successful grow rooms. We understand that evaluating design conditions, plant count, and equipment that will size properly in the growing space is not an easy endeavor. We also understand that indoor cannabis growing requires more than your traditional dehumidification process – it requires heating, cooling, and dehumidification. Desert Aire’s GrowAire™ solutions provide the integrated control of temperature, humidity and airflow conditions to enhance and protect crops.

Watch our videos below, including a case study of a licensed medical marijuana grow facility in Massachusetts and details of our products for small- and medium-sized cannabis grow room facilities.

The air conditioning needs to have required power to work properly. When purchasing an ordinary room air conditioner, it is enough to pick the cooling capacity according to the room size, or more precisely its volume. Normally, one cubic meter requires 30 watts of cooling capacity.

Essentially, there are two ways to cool air in the grow room. Either you take the warm air out of the cultivation space and replace it with cooler air from outside, or use air conditioning. The first option is widespread among home growers. The basic condition for its proper functioning is that the temperature of air sucked in or blown into the grow room is not higher than the temperature you want in your cultivation area. For a very basic installation, it is enough to have a sufficiently strong exhaust fan.

Most dehumidifiers intended for indoor use are primarily designed to remove average air humidity at normal room temperature. This is not enough for your grow room. But even a weak dehumidifier is better than none, and any active dehumidifier from the supermarket will suffice when growing on one square meter. In combination with air conditioning, even these ordinary dehumidifiers can work well in medium-sized growing tents. Nonetheless if you want a truly reliable dehumidifier for a large grow room, pick one from a range of manufacturers that focus on dehumidifying areas used for growing plants or on dehumidifying industrial premises.

Appropriate climatic conditions are essential on the road to a successful harvest – not only in regards to growing cannabis. However, maintaining these conditions is often a demanding task that both home growers and large producers need to solve. What happens most is that we have to cope with high temperatures and high relative humidity in our grow rooms. These two variables are closely linked and there are many ways to deal with them. In the following article we will examine them in greater detail.

Air conditioning

Air humidity is tells us how much water is contained in a certain amount of air that surrounds us. Most of you are probably familiar with measuring the air humidity with percent. This is the relative or proportional humidity of air, which expresses the ratio between the actual amount of vapor in the air and the amount that the air could absorb under the same temperature and pressure. If it were fully saturated with water vapor, the relative humidity would be 100%. The second widely used identifier is the so called absolute air humidity. It expresses the weight of steam contained in a particular unit of air – in Europe, the weight of water vapor in grams per cubic meter of air is most often used.

However, this is not enough when choosing the right air conditioner for the grow room. In this case, it is necessary to know how many watts are produced by lifting source, or by other installed devices (e.g. CO2 generator). If you have six 600 W sodium lamps in your grow room, you need a cooling capacity of at least 3 600 W.

The most reliable way to reduce moisture in your grow room is to use a dehumidifier. It can be used not only on its own, but also as a support for the dehumidification capacity of air conditioning unit. A dehumidifier has generally higher dehumidification capabilities than air conditioning with a dehumidification unit. There are several viable options when choosing a dehumidifier. Passive dehumidifiers with absorbent features are usually available in stores. These models are absolutely insufficient for indoor growing. Remember that almost 100% of the water you use to irrigate the plants is released back into the atmosphere as vapor. The larger the plants, the larger amount of water vapor needs to be drained from the air. This is achievable only when using active dehumidification.


The power of a given dehumidifier is usually measured in the amount of liters of water which it is able to remove from the air during 24 hours. It is advisable to check the temperature and relative humidity at which the dehumidifier is able to remove such amount moisture. What happens often is that the dehumidification capabilities are measured under conditions which you will never achieve in the grow room and which artificially increase dehumidification performance. An ideal scenario is when you know how many liters of water the dehumidifier can remove at temperature around 25 °C and a humidity between 60 and 80%.

It should have at least 40 times stronger air flow than the volume of the growing area. For 2 x 2 x 2 meter grow room, you would need a fan with air exchange power of 240 m3/ hour. Of course, there needs to be an opening in the grow room through which fresh air can be drawn in under pressure. For even more efficient cooling, install a second air intake fan. It can have half the power of the exhaust fan.