Does a Carbon Filter Have To Vent Outside? [3 Things You Should Know]

What a foul smell is this? Is it coming out of your grow tent? Oops! Are you feeling the same issue? If yes.think what are you missing?

We got it, there is no carbon filter here. Hurry up and get one!

Good, finally you got one!

What’s the biggest concern now, should it vent outside or inside? Hot debate…

Let’s read the article to get a quick answer to this confusing query!

Does a carbon filter have to vent outside? Yes, or no both, depending on your setup mainly. It can be vented outside if it is supposed to increase tent temperature. It can not be needed to vent outside as it is harmless, fresh, and pure to be reused by plants. However, if your tent is smaller and tightly sealed, it will automatically vent outside with filters placed totally out of the tent by following proper guidelines.

Basically, activated carbon filters help to reduce heat, odor, and contamination from grow tents. It can still work from outside but in this way, the temperature of your growing area will be difficult to regulate. Though if you put inline fans then you can control this issue.

Let’s move to the topic gradually!

Why Do You Need a Carbon Filter For Grow Tent

Is it your final decision to start your project in a grow tent? Have you collected all the essential equipment needed for tent installation and ventilation? Wait, wait, one thing is more. You can’t go further without installing a carbon filter. Why?

Grow tents are not much exposed to fresh air. That’s why there is a high tendency for the accumulation of harmful gases like carbon dioxide in a tent atmosphere which drops the quality of air. Though it has no direct effect on plant growth. However, this low-quality air tends to produce an unpleasant odor, allergic symptoms, and other respiratory issues for home dwellers. Carbon filters do the job of removing unpleasant odor by filtering carbon dioxide and other gases. Hence it not only helps to boost air quality but also makes it allergen-free for respiration.

The ventilation system only works to flow air in and out it has nothing to do with filthy gas particles. So, both ventilation and carbon filters work together to create a healthy environment for your plantation.

How Does Carbon Filter Work?

Before we move on, let’s discuss how this filter works actually? It really depends on how it is designed. Some filters are designed to set up exile after a fan through duct It works as an efficient absorber of odor particles allowing fresh air to come out through ventilation. It holds the adsorbate particles as a thin film and traps them to process again in the air. As a result, it purifies the inside air from any kind of contamination. These activated filters do the whole task air filtration task inside the tent atmosphere. So the air that comes outside is fresh and healthy to breathe.

It is designed to trap odor particles not to absorb.

Best Setup of Carbon Filter; Inside Vent or Outside Vent

Now you are fully aware of its importance. It’s time to know how to set up this filter? Vent Outside or Inside the grow tent?Though its answer is not as simple as the question itself is.

This device is always installed inside the tent. For tightly sealed grow rooms, growers often feel it difficult to install inside. Here you can go with the option of outside filter vent. But for good results, it is always recommended to install the device inside the tent and give it vent outside through a ducting. In this way, it will be 100 percent safe to use. But it requires rather complicated installation techniques. Inside setup is hazel free.

How to Stop Vent Outside When Carbon Filter is Placed Inside

Is it possible to provide an outside vent for a filter even so it is placed inside the tent? Yes, you can do it by ducting the fan plus filter through the hole that opens outside the tent. It is perhaps the most ideal SetUp. For this, follow the steps below –

  • First, open the Carbon filter and adjust the pre-filter with the help of elastic bands.
  • Now join intake fan at the end of the filter with  of the same diameter as filter end itself is
  • If your fan is attached to the outside ducting you can stop the outside vent by mounting a rubber coupler in the ducting to stop the airflow from the carbon filter to outside.
  • Now cut the duct measuring the distance of vent hole and fan
  • Attach the duct with the end of the fan and 
  • It’s time to fix both fans plus filter up on the inside roof of the tent
  • Now pass the duct that comes from a fan outside through the vent hole

This type of passive airflow mechanism is ideal to keep your plants happy and healthy.

Why It Is Not Necessary To Vent Carbon Filter Outside

If your filter is inside, you need not vent air coming out of the filter. Still some SetUp use outside ducts opening to allow fresh air to come in and recycled air to move out. But this is not as necessary to suck the air out of the filter and throw it outside. However, this type of ducting is essential to move warm air outside.

If your setup gets warm quickly then you can whale warm air outside. It happens when there is not enough inline fanning available. So ensure proper fanning, humidity, temperature check before and after the filter. If you fix want to keep.

There is no need to exhale air out of the filter but there is a great need to vent hot air outside the tent. Hope you got that point!

Why to Setup The Carbon Filter Outside

Ever heard Carbon filter outside? Not good, though it’s still possible to make Outside Setup. There are a few reasons to go for this option. Let’s move into the truth of the matter to know why growers want to install it outside

  • Smaller Size of grow tents is a strong reason to have a vent outside. Size of 2×4,4×4,4×8 is not big enough to hold these filters inside
  • Plant lovers do it to increase space in a growing area as it is a heavy object and occupies a lot of space when putting on the floor.
  • Sometimes grow tents are not strong enough to accommodate this heavy stuff. As it works best when hanging on the roof. But it’s impossible in low-quality tents.

Folk, go on with the option of outside vent setup if your tent is smaller, weaker and you need more space.

Editors Tips: How to clean the carbon filter? If you have a carbon filter already then Read it first to know how to clean it properly. If you don’t you can check out this iPower 4 Inch Air Carbon Filter Indoor Plants for you.

How to Set Up Carbon Filter Outside the tent

As you know you can provide an outside air vent to the filter that is placed inside the tent by connecting it to the duct that opens outside. It will facilitate passive airflow. Here we are talking about a totally outside setup in which the filter itself is outside. There are two ways to create it.

Let’s move to way number one!

1. Outside Carbon filter Setup While Fan is Inside

We’re going to guide you to make a surprising setup in which the fan would be inside and the filter will be out. You can go with this option if your growing enclosure is not strong enough or not too wider to accommodate such a heavy filter device.

Here are the steps!

1.Unbox the filter and adjust pre-filter by sliding plastic bands on it

  1. Select a suitable place away from pets or kids to place the filter near the tent. It should not be too far as lengthy ducting may drop its efficiency
  2. Insert inline fan and measure the distance between fan rim and filter.
  3. Cut the duct according to this length using duct cutter and attach it to the end of the fan with a wire loop 
  4. Bring this duct out of the tent through-hole(already they and attach its other end to filter.

(Note; Duct line or fan should be on the same side of the tent wall to reduce airflow)

  1. Finally, seal both duct joints with tapes or duct clamps

Your setup is ready now.

how to set up carbon filter outside grow tent

2. Outside Fan plus Outside filter SetUp

Sometimes, tents come with no hole or sealed tightly to accommodate any other device. In this case, growers put both fans and filters outside. This type of setup reduces inline fan noise. Let’s see step by step how they do it.

Here are the steps!

1. Select a suitable place near the tent to place a filter away from kids or pets.

  1. Put the tapered edge of the fan right above the filter and join it with duct wraps.

(Note: Get the fan-combo filter for this purpose as both fan and filter have the same diameter)

  1. Make a hole intent wall as it sometimes vents holes. Circumference of the hole should be the same as the diameter of the fan itself.
  2. Now measure the distance from the vent hole intent wall and the fan carefully. Cut the ducting of the same length that goes from vent to fan.
  3. Seal all the three joints like vent-duct joint,duct-fan joint, and fan-filter joint with duct clamps properly.

Disadvantages of Keeping The filter Outside

We told you earlier that it is possible yet not recommended. Outer filters can do the air filtration job properly. These procedures are risky somehow as there are kids and pets in many homes.Lets discuss a few technical disadvantages of this exhale filtration process!

  • Dust will be still there inside the tent as it is a basic function of pre-filter to suck dusty particles. So, outside Setup will not give expected results.
  • There is no way to throw contaminated air out of the filter in this setup. So, the filter will expire soon.
  • Fans may not work well to suck enough air inside if it is installed outside.SDucting through vent may also hamper airflow.
  • If the fan is outside, there would be no way to keep the tent cooler. It may catch fire also.
  • If the fan is outside, then there will be noise in your home that is frustrating anyhow.

Editors Tips: What Size Carbon Filter For Grow Tent? Read it first to know which size carbon filter is needed for you.

Safety Risk With Remedies

There are some safety risks attached to these procedures. But if you take measures seriously, you can avoid any hassle in the future. So, note down these risks and also read measures to handle them.

  • In the case of pets and kids, an outside fan option is not safe. If you still want it then arrange some hidden area for both of them
  • As we know this kind of assembling can increase pressure on fans. So, it is recommended to Use Circuit Breakers to avoid any damage
  • If both fan plus filters are outside then the pre-filter has nothing to do. You can install this prefilter at the opening to vent to make it functional
  • Use high capacity fans that will work longer than you expected

Bottom Line

We’re here at the end now. I would advise you not to try this outside filter installation technique. It is better to buy only those tents that are wide enough to accommodate filters inside. Always spend wisely and buy bigger grow rooms with a lot more options. What is your experience with filter installation? Share it with us in the inbox. We would love to reply and start an informative discussion.

Lisa Marshall

Hi, This is Lisa Marshall. Lisa has been working with farmers for over thirteen years. It is his passion, hobby and profession. To facilitate other gardeners from her experience, she has decided to start this website to share her gardening experience with her plant lovers.

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