Indoor cultivation requires very tight environmental control in order to maximize product quality and yield. To effectively control the indoor environment, both temperature and humidity levels must be addressed. This leads many cultivators down one of two paths. Dehumidification and cooling using an all-in-one system, or using dedicated cooling and dedicated dehumidification.
All-In-One AC-based Climate Systems
In all cases, an air conditioner of some sort must be used to control the heat load within a growing facility, which is generally very high due to all of the overhead lighting. Air conditioners will remove moisture – however their primary function is to cool the air. When the lights are on, AC systems will run a high percentage of the time and thus some moisture will be removed. However, when the lights go off and there is no longer a heating load to work against, the AC will turn off which ceases all moisture removal. Not a good thing!
Remember – for every degree temperature decreases, RH will increase by roughly 3% causing an unhealthy spike in humidity. This is a recipe for trouble when lights are off, and you’re not running dedicated dehumidification. The only way to combat this spike when utilizing an all-in-one AC based climate control system, is to re-heat the air in the space to create a load for the AC system to run against. This can lead to the system wrestling with itself and increased energy costs.
Dedicated Cooling & Dedicated Dehumidification
Dehumidifiers on the other hand are specifically designed to address the moisture in the air without cooling. They run totally independent of the air cooling system. For this reason, high efficiency dehumidifiers pair well with air conditioning systems of all types (split systems, chillers, mini splits and roof top units).
In most cases, the dehumidifiers will kick on periodically to assist the AC with the moisture load when the lights are on. However, they truly shine when the lights go off and the AC stops working due to lack of heat load. That’s when the dehumidifiers in a grow room perform some heavy lifting to prevent counterproductive spikes in RH. They maintain an ideal environment without over-cooling for optimal plant growth, quality and yield.
Redundancy is Key
Stakes are high in many grow facilities, due to the value of the indoor crop. Redundancy is important to reduce risk in the event of equipment failure. An all-in-one system leaves the cultivator vulnerable because if anything goes wrong the entire system is compromised. Service from a specialist is required right away or crop damage will occur. On the flip side, by using a dedicated cooling and dedicated dehumidification system the cultivator is protected by the inherent redundancy in the system. A typical dedicated dehumidification system will utilize multiple dehumidifiers. If one has an issue the remaining units will simply have to work a bit harder until a swap or repair can be made. In addition, if there is an issue with the AC system, the dehumidifiers will be able to control the RH levels while the system is being repaired.
As long as RH is controlled the potential for crop damage is minimal.