GorrillaGardener
New Member
As an English man the weather always seems to come to mind & right now the temperature has reached 30C here in my grow shop & I am just not used to it. So much so I had to take my clothes off! I put them back on again after the 3[SUP]rd[/SUP] customer came in & then left again in a hurry.
So that got me thinking about what you can do to cool your plants off in a grow room seeing as though they cant just strip off a layer of clothes like us humans. Generally once the temp goes over 30C (86F) things start to go wrong! Plants gasp for air & start to cook as you can see when they start to wilt & dry out.
The first thing you need to address is your ventilation? Is your ‘air intake’ fan big enough to supply an adequate air supply? Where are you taking your air from & is your outtake fan big enough to cope in summer. Do you need to change your growing/light cycle to the nighttime when it’s cooler? What about adding air conditioning?
These are all the things want to address, so lets start at adequate ventilation.
WHAT SIZE INTAKE FAN DO I NEED?
Ventilation is about controlling the quality of air, CO², heat and humidity in the grow room. To achieve a high quality of air in your grow room, you need to ensure that there is a sufficient amount of air exchange. The amount of air exchange required will vary according to the temperature outside. As a general rule, maximum winter ventilation rates rarely exceed 12-20 air changes per hour however, maximum summer air exchange rates can go up to 60 air changes per hour.
You must make sure you have the correct size fan to get the most out of it.
Simply follow these instructions - measure the growing environment, multiply together (height x length x depth) which give the cubic meter volume (m3/h)!
Multiply this figure by 60 & you have the size of the fan you need to change the air in the room 60 times an hour! (Allowing for when it gets really hot in the summer!).
WHAT SIZE EXTRACTOR FAN DO I NEED?
The extractor fan, also known as an exhaust or ventilation fan is the most critical fan in the growing area. The extractor fan needs to be bigger than the intake fan to achieve a positive pressure.
Example 1
1.2m x 1.2m x 2m = 2.88 cubic meters x 60 = 172.8 m3/h (cubic meters per hour!)
A 4” (100mm) Fan RVK100ET –A1 moves 175m3/h.
Example 2
2.4m x 1.2m x 2m = 5.76 Cubed Meters x 60 = 345.6 m3/h.
A 5” (125mm) RVK 125E2-L1 Fan moves 350m3/h.
Example 3
2m x 2m x 2m = 8 cubed meters x 60 = 480 m3/h
A 6” (150mm) RVK 150E2-L1 Fan moves 600m3/h.
Its best to get a slightly larger fan than you actually require!
CARBON FILTERS
Some people like to use a carbon filter if they are growing a particularly smelly crop, such as garlic. Filters can reduce the flow rate of a fan by up to 25%, so we should multiply our fan extraction rate by 1.33 to allow for this reduction.
EXAMPLE 1 - WITH A CARBON FILTER
1.2m x 1.2m x 2m = 2.88 cubic meters x 60 = 172.8m3/h
173m3 x 1.33 = 229.82m3/h.
A 5” (125mm) RVK 125E2-L1 Fan moves 350m3/h.
EXAMPLE 2 - WITH A CARBON FILTER
2.4m x 1.2m x 2m = 5.76 Cubed Meters x 60 = 345.6m3/h.
346m3/h x 1.33 = 460.18m3/h
A 6” (150mm) RVK 150E2-L1 Fan moves 600m3/h.
EXAMPLE 3 - WITH A CARBON FILTER
2m x 2m x 2m = 8 cubed meters x 60 = 480 m3/h
480m3/h x 1.33 = 638.4m3/h
A 8” (200mm) RVK 150E2-A1 Fan moves 750m3/h.
AIR INTAKE SOURCE
Another consideration is the position where you intake your fresh air from? Ideally from outside, away from the exhaust fans discharge of stale air. This can be problematic in this hot weather so taking air from an area inside a cooler building could make all the difference (say a hallway or basement).
AIR COOLED LIGHT REFECTORS
Air-cooled reflectors are great at keeping temperatures in you grow space down. They work by extracting air from the grow space over the hot grow lights hence cooling down the bulbs. This has an added advantage of allowing you to move your reflectors & bulbs down closer to the plants creating more lumens & penetration, which in turn creates higher yields!
COMPACT FLORESCENT LIGHTING (CFL)
CFL bulbs are a really great way to go! They throw hardly any heat & consume small amounts of electric. They have better penetration than LED’s & are a fraction of the price although you may need to add a sodium or dual spectrum 400w-1000w to finish off the flowering stage.
LIGHT EMITTING DIODES
LED’S create hardly any heat at all but they cost the earth & I don’t feel they have the penetration for taller plants. They would work well but you need quite a few in & around the crop.
AIR CONDITIONING
You could go one step further by simply adding air conditioning unit directly in the grow room if space allows or in the hallway or basement as mentioned above. If you haven’t got the room you could consider creating an air-conditioned lung room! This involves utilizing a spare room or constructing a space or even using a grow tent & using the air conditioning unit in there, cooling the air & there & then extracting from there into your grow room.
Of course some growers take the summer off & go on vacation choosing not to grow at all at this time of year. Whatever you decide to do I hope you found this article helpful.
So that got me thinking about what you can do to cool your plants off in a grow room seeing as though they cant just strip off a layer of clothes like us humans. Generally once the temp goes over 30C (86F) things start to go wrong! Plants gasp for air & start to cook as you can see when they start to wilt & dry out.
The first thing you need to address is your ventilation? Is your ‘air intake’ fan big enough to supply an adequate air supply? Where are you taking your air from & is your outtake fan big enough to cope in summer. Do you need to change your growing/light cycle to the nighttime when it’s cooler? What about adding air conditioning?
These are all the things want to address, so lets start at adequate ventilation.
WHAT SIZE INTAKE FAN DO I NEED?
Ventilation is about controlling the quality of air, CO², heat and humidity in the grow room. To achieve a high quality of air in your grow room, you need to ensure that there is a sufficient amount of air exchange. The amount of air exchange required will vary according to the temperature outside. As a general rule, maximum winter ventilation rates rarely exceed 12-20 air changes per hour however, maximum summer air exchange rates can go up to 60 air changes per hour.
You must make sure you have the correct size fan to get the most out of it.
Simply follow these instructions - measure the growing environment, multiply together (height x length x depth) which give the cubic meter volume (m3/h)!
Multiply this figure by 60 & you have the size of the fan you need to change the air in the room 60 times an hour! (Allowing for when it gets really hot in the summer!).
WHAT SIZE EXTRACTOR FAN DO I NEED?
The extractor fan, also known as an exhaust or ventilation fan is the most critical fan in the growing area. The extractor fan needs to be bigger than the intake fan to achieve a positive pressure.
Example 1
1.2m x 1.2m x 2m = 2.88 cubic meters x 60 = 172.8 m3/h (cubic meters per hour!)
A 4” (100mm) Fan RVK100ET –A1 moves 175m3/h.
Example 2
2.4m x 1.2m x 2m = 5.76 Cubed Meters x 60 = 345.6 m3/h.
A 5” (125mm) RVK 125E2-L1 Fan moves 350m3/h.
Example 3
2m x 2m x 2m = 8 cubed meters x 60 = 480 m3/h
A 6” (150mm) RVK 150E2-L1 Fan moves 600m3/h.
Its best to get a slightly larger fan than you actually require!
CARBON FILTERS
Some people like to use a carbon filter if they are growing a particularly smelly crop, such as garlic. Filters can reduce the flow rate of a fan by up to 25%, so we should multiply our fan extraction rate by 1.33 to allow for this reduction.
EXAMPLE 1 - WITH A CARBON FILTER
1.2m x 1.2m x 2m = 2.88 cubic meters x 60 = 172.8m3/h
173m3 x 1.33 = 229.82m3/h.
A 5” (125mm) RVK 125E2-L1 Fan moves 350m3/h.
EXAMPLE 2 - WITH A CARBON FILTER
2.4m x 1.2m x 2m = 5.76 Cubed Meters x 60 = 345.6m3/h.
346m3/h x 1.33 = 460.18m3/h
A 6” (150mm) RVK 150E2-L1 Fan moves 600m3/h.
EXAMPLE 3 - WITH A CARBON FILTER
2m x 2m x 2m = 8 cubed meters x 60 = 480 m3/h
480m3/h x 1.33 = 638.4m3/h
A 8” (200mm) RVK 150E2-A1 Fan moves 750m3/h.
AIR INTAKE SOURCE
Another consideration is the position where you intake your fresh air from? Ideally from outside, away from the exhaust fans discharge of stale air. This can be problematic in this hot weather so taking air from an area inside a cooler building could make all the difference (say a hallway or basement).
AIR COOLED LIGHT REFECTORS
Air-cooled reflectors are great at keeping temperatures in you grow space down. They work by extracting air from the grow space over the hot grow lights hence cooling down the bulbs. This has an added advantage of allowing you to move your reflectors & bulbs down closer to the plants creating more lumens & penetration, which in turn creates higher yields!
COMPACT FLORESCENT LIGHTING (CFL)
CFL bulbs are a really great way to go! They throw hardly any heat & consume small amounts of electric. They have better penetration than LED’s & are a fraction of the price although you may need to add a sodium or dual spectrum 400w-1000w to finish off the flowering stage.
LIGHT EMITTING DIODES
LED’S create hardly any heat at all but they cost the earth & I don’t feel they have the penetration for taller plants. They would work well but you need quite a few in & around the crop.
AIR CONDITIONING
You could go one step further by simply adding air conditioning unit directly in the grow room if space allows or in the hallway or basement as mentioned above. If you haven’t got the room you could consider creating an air-conditioned lung room! This involves utilizing a spare room or constructing a space or even using a grow tent & using the air conditioning unit in there, cooling the air & there & then extracting from there into your grow room.
Of course some growers take the summer off & go on vacation choosing not to grow at all at this time of year. Whatever you decide to do I hope you found this article helpful.
