What should I do with the temperature control scheme for grow room?

Controlling heat in the grow room

The least expensive way of reducing the heat in the grow room is to vent out the heat and replace it with cooler air. Sounds simple right? Well it is, but what most beginners forget is that you can't blow the hot air out without a way for the cool air to get in to replace it. The best way to setup a venting system like this is to mount one exhaust blower on the inside of the grow room up high to blow the heat out, and another blower on the outside mounted down low blowing cool air in. Hot air rises, cool air settles.

Exhaust blowers are rated or sized in Cubic Feet per Minute (CFM) of air, like "265 CFM". This is the amount of air the blower will move in one minute without any restrictions on the intake or exhaust. If a blower is rated at 265 CFM but it's connected to a 25 foot long tube like a dryer hose, it's not going to move 265 CFM because of the resistance in the hose. Aluminum tubing with smooth inside walls creates less resistance and the blower runs more efficient. So what size blower should you get? Well it just depends on how fast you need to exchange the air. If your grow room is 6 feet wide, 6 feet long and has an 8 foot ceiling you have 288 cubic feet of air in the room (6x6x8=288). So if your blower is rated at 265 CFM, and it has no restrictions on the intake or exhaust side, it should take about a minute to replace all the air. Of course if the air your replacing it with is already hot, it doesn't do much too cool the grow room. So it's best to draw cool air from outside.

The exhaust blower can be turned on with a thermostat so it only runs if the temperature gets too high. The thermostats plug into the wall and have an outlet for the blower. When you set the temperature at, let's say 80 degrees, the blower will turn on at 80 degrees. It will stay on until the temperature drops to 80 minus the differential. The differential is the difference between the turn on point and the turn off point. It's usually about 4 degrees. This means that if the thermostat is set at 80, the blower will turn on at 80 degrees and turn off at 76 degrees. This gives the blower some working time. If the thermostat had no differential the blower would turn off as soon as it turns on, then off, then on, etc., not very efficient.

Some people turn the blowers on with a timer. The blower might be set to turn on at a specific time or multiple times during the day. This will also get the job done, but it's not the most efficient method. If you're looking to control the temperature you should measure the temperature, not the time of day.

Sometimes the air coming in is just too hot and can't cool the room. When this is the case the blower can be run on the same timer as the grow light, or another timer set to go on at the same time. This is not really solving the problem, just a cheap fix. The problem is the air coming in is too hot, so why not cool it. An air conditioner can be used for the supply air and a blower can blow out the heat.

An alternative to moving all the air out is to capture the heated air and vent it. This can be done with an air cooled grow light. The advantage with this setup is that you're using less energy to move the heat out. The volume of air in the reflector might be 3 cubic feet and you can vent it out in a few seconds. It doesn't matter if it's hotter, just how much of it you have to move. Venting a 288 cubic foot grow room that's 95 degrees takes a lot longer than venting a 3 cubic foot reflector that's 150 degrees.
What is the Right Temperature and Humidity in the Grow Room?

The right temperature in a grow room will also depend on a number of factors. For instance, this could be affected by its location and the plants that you are cultivating. In the case of cannabis, the temperature should be ideally from 68 to 77 degrees Fahrenheit. When the plants are older, they can handle a temperature that is up to 82 degrees Fahrenheit. This is when the lights are turned on.

On the other hand, when the lights in a grow room are turned off, the ideal temperature should be anywhere from 62 to 72 degrees Fahrenheit. Keep in mind as well that the temperature during the day and night should not have too much of a difference.

Meanwhile, for the right level of humidity, keep an eye on the stage of growth of the plant. If they are seedlings or clones, the right humidity should be anywhere from 70 to 75%. For the vegetative stage, on the other hand, it should be from 50 to 70%. During the flowering stage, see to it that the humidity is kept at 40 to 50%. Finally, when it is about ready for harvest, the humidity should be anywhere from 45 to 50%.
How to Pick the Best Temperature and Humidity Controller

As you start shopping, take note that the products that we are talking about in this post are different from temp controlled box mods. You might also encounter the words temp control tank. The latter is a product for vaping while those that are mentioned in this guide are for gardening.
Ease of Use: Make sure that it comes with a user-friendly design, which will allow you to set the desired temperature without the need to exert effort.
Durability: See to it that it is made of long-lasting materials. One of the most important is to have an enclosure, often made of plastic, which will offer protection from external factors that could cause damage to the internal components.
Display: A good choice would be one that comes with an easy to see the display, which should show the current temperature/humidity as well as the temperature/humidity that you have set.
Alarm: The controller must make a loud sound to immediately notify you once the temperature/humidity has exceeded or gone below the threshold that you have set.
Warranty: Most of the options that we have listed down in this post have a warranty that lasts from one to three years. It will be good if the product has a longer warranty against defect so that you can be confident about its quality.
How to Effectively Manage Temperature and Humidity in the Grow Room

Before we proceed with the list of our recommended products, allow me to share with you some valuable tips on how to manage the temperature and humidity to make sure that it will optimize the growth of plants in an enclosed environment:
Sealing and insulating the room will prove to be necessary. This will provide an assurance that the temperature inside will be maintained and will not be affected by the temperature outside. Heat won't be able to escape, so as the cold. Otherwise, there can be fluctuations in temperature that will be beyond your control.
Air movement will also be critical. This is why you will need to install fans that will provide the necessary ventilation. Even floor fans will help. You should know when to turn on the fans and when to turn them off. Pay attention as well to oscillation, making sure that the air moves.
Be careful about the use of grow lights. While they are indeed necessary for photosynthetic activity in the case of plants that do not receive sunlight, they could also add up to the heat. This can cause a rise in temperature that can affect the health of the plants. Make sure to choose grow lights that do not make the grow room hot.
It is also recommended that you use a humidifier/dehumidifier in the grow room, depending on whether the humidity is too high or too low. One of the keys to the success of this step is to size it properly. Otherwise, it will only end up wasting electricity without doing anything good to your plants.
You can also use heating and cooling equipment to control the temperature in the grow room. A heat mat or a heater fan can be a great choice if you want to increase the temperature. On the other hand, if you want it to be lower instead, you can use a compact air-conditioner or a circulator fan.
What is a grow room controller?

A grow room environmental controller allows a grower to automate their grow. Using a combination of these controllers, or one multi-function controller, allows growers more time away from the grow room! Human error is a common cause of most problems in the grow room or grow tent, and environment controllers cut down on this drastically.

Utilizing an environment controller allows growers to monitor different aspects of the grow room essential to plant health, such as heat, moisture and humidity, fan speed, CO2, and grow lights. These devices allow you to ensure optimal growing conditions without actually monitoring them in person! Simply set the timers and controllers to the ideal range and hours, and let them do the work, granting you more freedom outside the garden!
What types of grow room controllers are there?

For serious indoor growers, we recommend a multi-function grow room controller, which monitors temperature, CO2, humidity, and even lights, all in one!

If you only need to automate a certain component in your grow room, rest assured we have it here!
Temperature Controllers- These controllers monitor temperature in your grow room, through either fans, air conditioners and heaters, or both!
Humidity Controllers- Humidity is an important aspect of your grow room, and these controllers maintain optimal humidity levels by powering on and off humidifiers and dehumidifiers
Fan Speed Controllers- Odds are, you don't need your fans blowing at the same level at night as you do during the day. These controllers allow you to set various fan speeds depending on the time!