Do carbon filters go bad?

aeviaanah

Well-Known Member
First off, I just bought a used carbon filter, do they go bad? How long do they last?

Will an old one be better than none at all?

Will i lose airflow using a carbon filter? I also bought an inline fan to correct this problem. How would one figure out how much cfm required for a certain carbon filter? Can anyone point me in the right direction?
 

Mother's Finest

Well-Known Member
How long they last depends on airflow and pollutants in the air. They do go bad. Activated carbon absorbs many substances from the air and will eventually become saturated with them. It might be hard to test one before getting it home, but you can of course tell if it's working after hooking it up by smelling its exhaust. If there are no plants growing yet then cook something and see if the smell gets through.

Yes, you lose airflow with the filter but if the filter is big enough, the loss will be minimal. If you can't look up the model's reccomended CFM's online, the size of the inlet & outlet should give you an idea of what size blower it was made for. You can also just look up similarly sized filters online and see what their suggested fan sizes are.
 

researchkitty

Well-Known Member
I replace the carbon in my filters once a year. They just become less effective over time as the product it removes from the air stays in the filter and over time those pores become less effective the more that they fill up.

You dont replace the entire filter, just the carbon inside of it. Your local hydro store probably has it in stock, or eBay for half the price................
 

aeviaanah

Well-Known Member
they dont go bad, they just stop working as the coal looses its effectiveness.
thankyou
How long they last depends on airflow and pollutants in the air. They do go bad. Activated carbon absorbs many substances from the air and will eventually become saturated with them. It might be hard to test one before getting it home, but you can of course tell if it's working after hooking it up by smelling its exhaust. If there are no plants growing yet then cook something and see if the smell gets through.
right on bro, this is a good idea.
Yes, you lose airflow with the filter but if the filter is big enough, the loss will be minimal. If you can't look up the model's reccomended CFM's online, the size of the inlet & outlet should give you an idea of what size blower it was made for. You can also just look up similarly sized filters online and see what their suggested fan sizes are.
i will do this before i haul the heavy fucker up the attic. ill have someone burn a bowl and blow it into inline fan ducted to another room that has the carbon filter.
I replace the carbon in my filters once a year. They just become less effective over time as the product it removes from the air stays in the filter and over time those pores become less effective the more that they fill up.

You dont replace the entire filter, just the carbon inside of it. Your local hydro store probably has it in stock, or eBay for half the price................
Right on kitty thanks, ill be sure to test it first then go ahead and replace the carbon. Ive noticed there is two different looks to the carbon, one is like an australian carbon and the other is like cylindrical looking stuff. have you tried both? do you have a preference?
 

dart420

New Member
thankyou

i will do this before i haul the heavy fucker up the attic. ill have someone burn a bowl and blow it into inline fan ducted to another room that has the carbon filter.

have someone who doesnt blaze smell the exhaust and join your buddy!!!!!!! i can really only smell burnt herb first thing in the morning befor i have blazed, after that its pretty regular so if your the same then make sure its working. i have my wife poke her head in the attic every now and then just to make sure its working. just a thought.
 

woodsmaneh!

Well-Known Member
I replace the carbon in my filters once a year. They just become less effective over time as the product it removes from the air stays in the filter and over time those pores become less effective the more that they fill up.

You dont replace the entire filter, just the carbon inside of it. Your local hydro store probably has it in stock, or eBay for half the price................
There are different quality's of carbon available and I find it pays to do some home work on what you refill them with. That's why some filters are $50 and some are 100$ There is a big difference in how long they last.

To ensure total air filtration, there are several important factors to consider. The first and most important factor is the carbon grade choice. Grade RC-48 carbon is derived from an ancient black coal deposit found only in Western Australia. This particular deposit is dated at over 250 million years old.

After being extracted, the RC-48 carbon is kiln activated at 1200° C in a saturated steam atmosphere. It is this process together with the coals unique density that causes the pores in the carbon to form. This activation process makes the RC-48 carbon incredibly effective for the filtration of organic particles and other airborne materials.
 

researchkitty

Well-Known Member
I never thought about re-activating my own carbon. Could I do this myself if I had an oven at 1200? (I do, I have an oven that will go to 1725(F) for glass blowing).

As for carbon type, activated carbon is fine. Sure, some carbon is twice the price or half the price, but the goal is smell removal. If it does that, then its good carbon. :) Every seller of carbon will tell you how theirs is the best because of many minute technical reasons that differ between brands.............. Is there any substance to it? I've never been able to tell, and I go CHEAP on replacement carbon, and it seems to work as well as what was in the CAN filters when I bought them, so............. Remember too, me replacing carbon is because of using it for 12 months for 6 lights full time. Chances are you wont really go through it as fast as I do on a commercial scale..........

When it starts to stink, replace the carbon.
 

Hidden Door

Member
i've had good results by baking my carbon in my household oven's self cleaning cycle. i bet your oven would make it like brand new.

I never thought about re-activating my own carbon. Could I do this myself if I had an oven at 1200? (I do, I have an oven that will go to 1725(F) for glass blowing).

As for carbon type, activated carbon is fine. Sure, some carbon is twice the price or half the price, but the goal is smell removal. If it does that, then its good carbon. :) Every seller of carbon will tell you how theirs is the best because of many minute technical reasons that differ between brands.............. Is there any substance to it? I've never been able to tell, and I go CHEAP on replacement carbon, and it seems to work as well as what was in the CAN filters when I bought them, so............. Remember too, me replacing carbon is because of using it for 12 months for 6 lights full time. Chances are you wont really go through it as fast as I do on a commercial scale..........

When it starts to stink, replace the carbon.
 

woodsmaneh!

Well-Known Member
I never thought about re-activating my own carbon. Could I do this myself if I had an oven at 1200? (I do, I have an oven that will go to 1725(F) for glass blowing).

As for carbon type, activated carbon is fine. Sure, some carbon is twice the price or half the price, but the goal is smell removal. If it does that, then its good carbon. :) Every seller of carbon will tell you how theirs is the best because of many minute technical reasons that differ between brands.............. Is there any substance to it? I've never been able to tell, and I go CHEAP on replacement carbon, and it seems to work as well as what was in the CAN filters when I bought them, so............. Remember too, me replacing carbon is because of using it for 12 months for 6 lights full time. Chances are you wont really go through it as fast as I do on a commercial scale..........

When it starts to stink, replace the carbon.

Soak in strong NaOH solution. Rinse very well with water. Than heat. O ya for those of you who missed chemistry class that day, NaOH, Sodium hydroxide also known as lye and caustic soda.

 

aeviaanah

Well-Known Member
thankyou

i will do this before i haul the heavy fucker up the attic. ill have someone burn a bowl and blow it into inline fan ducted to another room that has the carbon filter.

have someone who doesnt blaze smell the exhaust and join your buddy!!!!!!! i can really only smell burnt herb first thing in the morning befor i have blazed, after that its pretty regular so if your the same then make sure its working. i have my wife poke her head in the attic every now and then just to make sure its working. just a thought.
Right on, ill be sure to do this before attempting to haul up the attic!
There are different quality's of carbon available and I find it pays to do some home work on what you refill them with. That's why some filters are $50 and some are 100$ There is a big difference in how long they last.

To ensure total air filtration, there are several important factors to consider. The first and most important factor is the carbon grade choice. Grade RC-48 carbon is derived from an ancient black coal deposit found only in Western Australia. This particular deposit is dated at over 250 million years old.

After being extracted, the RC-48 carbon is kiln activated at 1200° C in a saturated steam atmosphere. It is this process together with the coals unique density that causes the pores in the carbon to form. This activation process makes the RC-48 carbon incredibly effective for the filtration of organic particles and other airborne materials.
So is this the initial process before they sell it, or/and a way to reuse it?
I never thought about re-activating my own carbon. Could I do this myself if I had an oven at 1200? (I do, I have an oven that will go to 1725(F) for glass blowing).

As for carbon type, activated carbon is fine. Sure, some carbon is twice the price or half the price, but the goal is smell removal. If it does that, then its good carbon. :) Every seller of carbon will tell you how theirs is the best because of many minute technical reasons that differ between brands.............. Is there any substance to it? I've never been able to tell, and I go CHEAP on replacement carbon, and it seems to work as well as what was in the CAN filters when I bought them, so............. Remember too, me replacing carbon is because of using it for 12 months for 6 lights full time. Chances are you wont really go through it as fast as I do on a commercial scale..........

When it starts to stink, replace the carbon.
Right on thanks!
i've had good results by baking my carbon in my household oven's self cleaning cycle. i bet your oven would make it like brand new.
Right on, there is a noticeable difference before and after?
Soak in strong NaOH solution. Rinse very well with water. Than heat. O ya for those of you who missed chemistry class that day, NaOH, Sodium hydroxide also known as lye and caustic soda.

Thanks for the great idea! Good information...a quote provided too! Thanks. +rep.
Mother pointed out that most filter sites will have a calculator for determining the size you need. I don't use Phresh, but I like their calculator enough to share it. http://www.phreshfilter.com/selector.php
Right on thanks! Nice calculator, ill be sure to take a look at it before installing this thing. +rep.
 

Captain Curry

New Member
I just noticed a light smell starting to come from my exhaust. I have a huge can filter and its been almost but less then a year of running it at 24/7. I started running a scubber in the room full time as well but I could still get a hint of a smell. Im wondering if taking off the slip that covers the holes on the filter would help in the short term? It looks really dirty, could that be messing things up?
 
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