Will there be too much heat ???

Currently designing a grow room for a 2000m2 room, it consists of 40 gavita lights, I have 150L of dehumidification available, I’m also running 3x 4250m2/h box fans for extraction of air from the room, my question is will I be having issues with heat from all these lights? Even though my outside temperature isn’t very high, I’m going to be able to pull fresh air into the room and exhaust the old hot air out, into a seperate room, what is the best cost effective way I can stabilise the temperatures in the grow room ? Especially at night because the place can get cool, especially during the winter, will I need to add heaters for nighttime ? Many thanks

To really know, you have to run as you have stated a couple days and determine temperatures at various times. Obviously it will change with the seasons, so be aware. I would recommend running lights at night in order to use the heat from lights to your advantage. Also be advised large volume air flows can change temperature and humidity quickly and can result in large undesirable swings. Closely monitoring is key until you have faith in the setup. Every setup characteristics and nearby climate factors make it difficult to determine at this point.

Yes I think running lights during nighttime will definitely help during the winter months, is there anything else you can think to minimise these undesirable swings, I’m going to be installing some fan controllers to help with the heat. But as you said I think a lot of it will just be trial and error playing around with it until get comfortable with it, I hope it’s not going to be so unmanageable and I’ll have to get 2-3 mini split AC installed.

Biggest external factor is your outdoor climate. Use the light heat to your advantage and watch for chasing a number with multiple appliances unless they are controlled by single controller. It is such a large space, you will need to take several measurements.

Recodotz said:

Currently designing a grow room for a 2000m2 room, it consists of 40 gavita lights, I have 150L of dehumidification available, I’m also running 3x 4250m2/h box fans for extraction of air from the room, my question is will I be having issues with heat from all these lights? Even though my outside temperature isn’t very high, I’m going to be able to pull fresh air into the room and exhaust the old hot air out, into a seperate room, what is the best cost effective way I can stabilise the temperatures in the grow room ? Especially at night because the place can get cool, especially during the winter, will I need to add heaters for nighttime ? Many thanks

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Calculating the airflow required to maintain a stable temperature, and so determine the size of fan needed, is surprisingly simple.

It boils down to CFM = 3.16 x Watts / DT(°F)

Watts is the lighting power (and any other 'hot' things in the grow space) in Watts.
DT is the allowable temperature rise within the enclosure (i.e. desired temperature minus ambient temperature) in °F.

So, to work out the size of fan required (in CFM) simply plug your lighting Wattage into the equation along with the DT value.

An example is:
Ambient temerature = 20 °C
Target temperature of the enclosure = 25 °C
DT in °C = 25 - 20 = 5
DT in °F = 5 x (9 / 5) = 9
Lighting Wattage = 250 Watts

Plugging these values into the equation gives:

CFM = 3.16 x 250 / 9 = 87.77