How Much Grow light Cooling do I Need?

Cooling grow rooms is a complicated task.  When designing your grow room you probably are asking yourself “how much cooling do I need for my grow lights?”  There are a variety of factors that can cause heat loads in grow rooms to rise unexpectedly. It is important to give yourself a little leeway incase some of the electronics produce more heat than expected.

There are a variety of lights you can choose to grow with. LED lights have came along way in quality since being first introduced over a decade ago. High end LED lights now produce less heat and are on PAR with HPS light intensity. High end LED lights have been taking over the cannabis industry as a standard in most dispensary grow rooms.

They can be easily mounted on any flat service which makes them great for new vertical grow rooms. Vertical grow rooms have been increasing in popularity due to the fact they can increase the space of your grow room greatly.

HPS lights have been a favorite for Veteran Growers for the past 30 or more years due to the reliability of flower yields.  A little tip to make your buds bigger is More Light = Bigger Buds. The hardest part about adding more than enough light is keeping the room at a decent temperature. Most cannabis strains like it around 65-80 degrees when you are running HPS Lights. When growing with LED lights. Cannabis strains tend to do better with temperatures in the low 80’s.

Metal Halide lights produce a white spectrum of light compared to the yellow tint of HPS. Metal Halide lights also usually produce a little more heat in my experience. Metal Halide lights are best used in a Veg Room, and HPS are more used in Flower. Metal Halide spectrum has been known to keep plants looking lush in vegetation.

One of the most important factors of grow room lighting is the WATTS the light produces. I have seen some of the new high end LED lights producing about 65% of the heat compared to HPS lights with the same wattage. HPS and Metal Halide lights both require a external ballast to power the lights. Lighting Ballast produce heat too. You can mitigate the heat of a external ballast from your grow room by placing them outside of the grow room in a separate room. You can use lighting extension cords placed in cutout through the wall to power the lights this way. If you must place your ballast in the grow room just remember to account for them in the heat load calculations.

BTU’s are British Thermal Units, and are the unit of measurement of what heat is measured in.  A single BTU is the amount of energy required to cool or heat a pound of water one degree Fahrenheit. 12,000 BTU’s are the same as 1 ton of air conditioning. 24,000 BTU’s are a 2 ton AC, and so on. One 1000w HPS light plus a ballast needs almost 1 ton of AC depending on the size of your grow area.

There’s a variety of tools online that can help you determine the heat load requirements in your grow room. One of my favorite free tools to use for grow room heat load calculations is by Hawthorne. This tool is a great way to quickly add up all your main heat sources in your grow room. Make sure you account for any items that produce heat like dehumidifiers and controllers too. Some things produce more heat than others so always remember to go a little bigger when sizing your HVAC. It is better to have a HVAC unit capable of more cooling than not enough cooling.

Hope this article helped with your question of “How much cooling do I need for my Grow Lights?” We at Hydro AC provide HVAC services for Arizona Grow Rooms. So please feel free to reach out if you need some help with your HVAC systems if you are a Arizona Grower.



Leave a Reply

Avatar placeholder

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.