One of the biggest challenges our customers face is extremely high humidity at night vs. the daytime. The basic reason for this is air temperature. When the air is warm it’s capable of holding a lot more vapor (water) vs. cooler air that can hold far less.
RH or relative humidity is just that, the humidity is relative to the air temperature. In basic terms there is no more or less “water” in the room between day and night but the massive impact is when it’s vapor it won’t affect the plants the same way as condensed water droplets sitting on the leaf or raining down from the ceiling. Conditions mentioned lead to mildew, rot and many other nasty side effects. The main way to combat this swing in temperature is to implement dehumidification along with several other helpful strategies.
Dehumidifier
Whether it’s a complete solution like our Evolution Series or a standalone dehumidifier having a system and solution in place is critical to driving down the humidity. Often rooms with properly sized A/C during the day cycle will always be lower when heading into the night cycle as a large portion of the load is removed through the A/C. We generally find rooms running appropriately sized systems during the day will run around 60-70% at night vs. 80-90% without A/C in the day cycle. When deciding on a standalone dehumidifier just know the byproduct of dehumidifying will be heat so your “off” room will slowly raise in temperature to the point your A/C may be battling your dehumidifier operating very inefficiently which is why our Evolution Series with the ability to flip seamlessly on the fly between modes would be your best option.
Airflow
Having adequate airflow throughout your space both during the day and night is extremely important for a balanced room. Ducting is always highly recommended, but more importantly properly engineered ductwork such as our Fabric Air ducts will eliminate hot and cold spots. We recommend keeping your indoor air handler fan running 24hrs per day to circulate the air continuously and evenly throughout the space. The other benefit is you can integrate a UV-C purifier inline so that the air will be constantly scrubbing airborne pathogens, killing spores, bacteria and mildew while keeping your humidity lower.
Sunrise/Sunset
We have found with many of our customers particularly ones with full automation, charting and diagnostic setups that they want to remove as many of the peaks between day and night humidity as possible. A successful strategy has been to implement a sunrise and sunset within their lighting system. This is accomplished by having several stages of lights turning off over the course of 30-60mins during transition day/night cycles. What this achieves is a slower drop of temperature from day to night rolling the peak more evenly. Additionally, you can have additional dehums increase the load by running the humidity percentage even lower than standard daytime to give a head start going into the night cycle. When transitioning to daytime the same process occurs staging lighting over a 30-60min period, again lessening the impact of temperature, allowing the systems to load up over a period of time.
We noticed over the past 3 years in particular yields continue to increase which means overall humidity loads continue to increase. Be thoughtful in designing your space to provide a constant environment 365 days a year.
