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HVAC Humidity Control In Cannabis Cultivation – The Quest for Precision

Harvest Integrated


The cannabis industry is booming, and with it, demand for the crop. But higher demand means that cannabis operations sometimes fail to keep their crop free from contamination. 

Just look at how mold continues to be a pain for many growers. In 2019, mold rocked Denver’s cannabis market after 80% of 25 dispensaries failed random mold tests. During that same year, a licensed cannabis testing facility in Nevada had to close after samples obtained from the facility failed secondary testing for mold and other fungi.

Fast forward two years later and cannabis sold in Nevada has, once again, failed yeast and mold testing while Colorado authorities had to recall cannabis because of alleged mold and yeast contamination. 

These markets are hardly the only ones where mold and other fungal contamination continue to disrupt operations and reduce consumer confidence. But why is mold such a big problem?

Why is mold such a big issue in cannabis grows?

Possible contamination from mold is a constant battle in grow facilities. This is because mold is a common problem whether cultivation is taking place indoors or out, plus mold favors the conditions that are prevalent in cannabis grows.  

Cannabis plants transpire as they go through the lights-on and lights-off cycle, creating a lot of moisture in the process. Left unchecked, this moisture content increases humidity and creates the perfect environment for contaminants such as mold to thrive.

Therefore, cannabis grows require precise control of the environment. Alongside light, temperature, airflow and CO2, humidity control is critical for the health of your crop. But not all HVAC systems are created the same, and it’s important to keep this in mind when thinking about precision in your grow facility. 

Why conventional HVAC systems won’t do for humidity control

Traditional HVACs are mostly designed for comfort cooling control in residential or industrial environments. This is where the problem starts. These systems can control temperature and humidity to a certain extent, but the fact is they are not designed to remove enough moisture to control humidity in a cultivation facility where plants are constantly transpiring and pushing humidity upwards. 

And humidity is high in cannabis grow spaces! Consider heat sources such as electrical machinery and grow lighting, for example. Both increase temperatures and transpiration rates, and this transpiration results in massive amounts of humidity.

The issue is that conventional HVAC systems are for cooling and so they attempt to reduce humidity by doing what they do best – cooling. To cope with the high humidity levels in a grow space, a traditional HVAC will continue to cool the space, driving temperatures too low and creating the need for reheating. This entire process requires a lot of energy and it’s inefficient. Put simply, expecting precise humidity control from a conventional HVAC system is asking for a lot. 

Cannabis is very particular about the environment in which it thrives. Temperature and humidity must be set within specific ranges (something you will struggle to get with traditional HVAC) otherwise your crop will suffer. Creating the optimal grow environment requires a solution that’s tailored to grow environments. 

Specialized HVAC humidity control – Achieving precision and efficiency

The best HVAC system for cannabis cultivation is one that is specifically built with cannabis in mind. Forget comfort cooling air conditioning that’s been tweaked to try and fit into a cannabis facility – that just won’t cut it if you mean business and growth.

A specialized HVAC system helps you create the optimal conditions, supporting plant growth on one end while preventing unwelcome and problematic elements problems such as mold, pests and pathogens from taking over. Getting the environmental conditions right in cannabis cultivation is a tough balancing act that relies on achieving precision, but specialized systems make this simpler. What’s more, they help you achieve precise humidity control with efficiency, no matter the scale.  

Choosing a specialized HVAC system

Although specialized HVAC for cannabis is growing in popularity, it’s still in its infancy. Basement grows were the norm for so long and technology that enhances cannabis cultivation is only starting to take form now (hence all the gaps in the specialized HVAC space). You will find that some “specialized” systems may still require additional pieces of equipment to remove excess moisture from the space. The need for additional pieces of equipment has its drawbacks, for example:

  • The cost of a system that relies on a lot of additional bits of equipment may be costly in the long term. It’s not only about the cost of acquiring the system, but about other elements such as integrating and installing the system as well as the cost of maintaining all the various equipment, which will likely be from different suppliers. 
  • A lack of integration can result in inefficiencies such as high energy consumption.
  • One word – clutter. Having to bring together many moving parts, as opposed to one system that takes care of a space’s environmental needs, can result in a lot of clutter

Fortunately, some HVAC manufacturers are making strides in the specialized systems space, 

  1. changing how growers handle HVAC humidity control;  and 
  2. challenging the monotony of traditional commercial HVAC design and construction. 

With a deep understanding of cannabis cultivation and what it takes to create the optimal grow space, these HVAC manufacturers are creating systems that offer a more flexible yet precise range of control on grow room environmental elements. Importantly, these systems are doing so without excessive energy consumption and they are helping cut down operating costs. 

Harvest Integrated is one of the leaders in HVAC humidity control in cannabis cultivation, offering an integrated system that’s built with cannabis in mind. Harvest Air™ packaged dehumidification and cooling systems are exclusively built for handling the specialized and demanding environments of the greenhouse and indoor cannabis industries. The systems ensure the highest performance and precision when it comes to cannabis facility climate control, and particularly humidity control. 

And to help bring you up to speed, here’s a quick rundown of the Harvest Air™ features that help growers achieve precise humidity control:

  • Precise dehumidification and cooling: The system is designed to handle dehumidification in cannabis environments. Additionally, the system comes with precise cooling and both capabilities are packaged in a single unit.
  • Variable speed compressors: The compressors keep a cannabis facility running even when the outdoor environment is hot and humid. Since outdoor humidity has an impact on the humidity in a grow space, the variable speed ensures that the HVAC matches the dehumidification and cooling load at every stage of the grow cycle for maximum efficiency. 
  • Built-in redundancy: Multiple compressors, motors and circuits ensure that a grow facility continues to enjoy precise humidity control even through a component failure. 
  • Ease of installation: Each unit comes to a grow facility fully packaged and factory-tested. Growers can start enjoying precise HVAC humidity control immediately without having to worry about system assembly or any costly field/piping charging.  

The best part about Harvest Integrated is that you don’t have to settle for a one-size-fits-all approach to HVAC humidity control. Based on the understanding that each cannabis facility is unique, with its own set of distinct challenges and demands, the Harvest Integrated team will work with you to design a system that specifically produces the best results and efficiencies for your grow. 

Related Content: Growing your cannabis in an open greenhouse? There’s a case for sealed greenhouse cannabis cultivation.

Precision, and even more precision

As the cannabis industry continues to grow, so too must the systems and technologies supporting it. Gone are the days of relying on imprecise HVAC systems borrowed from industrial and residential spaces. The industry has simply outgrown these technologies and specialized systems are the future. 

Although completely eliminating mold, pests and pathogens is difficult in any cannabis grow space (or any cultivation space for that matter), specialized HVAC is making things easier and redefining how growers control and regulate the grow environment. 

HVAC humidity control – The bottom line

The cannabis industry may be growing, but running a cannabis grow operation means having to deal with a lot of issues. From financing issues to tight regulations and establishing a good market share, there’s no shortage of problems that need to be addressed. As such, it makes sense to simplify and streamline processes wherever possible. 

A good place to start is by using a specialized HVAC system. This way you can optimize your cannabis grow space, giving you room to focus on other aspects of the operation without worrying about the quality of your crop and yields. 

In need of a specialized HVAC system that will help you grow your operation faster. Get in touch with our team, and let us help you build a tailored system that works for you.