Temperature VS Carbon filter performance

[FRANKIE1579]

In the past I have always hooked up my carbon filters like this

Air flow >>>>>Reflector>>>>>>Centrfg Fan>>>>>>Carbon Filter.

The reason I had my rooms set up in this manner was that the carbon filters also acted as mufflers for the exhausting air. No exhaust noise could then be detected from a distance.

Now we all know the issues regarding humidity and carbon filter performance.

I have always had serious odor control problems. My humidity stays at 40%. I have used Mountain Airs, Can Fans, Phresh, you name it I have tried it. I am not using a oversized fan per filter. I use a 435 CFM Fan per 600 CFM filter. I still have odor problems.

I have used high powered Corona Discharge ozone generators. I have never achieved a balance between no noticeable odor (electrical/storm smell) from the ozone generator, to no noticable odor from the plants. Its either one or the other. I do give the ozone as much time as possible to do its work. But when you are talking seriously large volumes of air its hard if not impossible to give it enough time (several minutes plus) before it is vented into the open.

Ona Gel is out. The amount you must use to conceal large grows make it not very cost effective or efficient.

I have been baffled by reading online how some people have ZERO odor control problems with carbon filters. And some, like myself, with the same filter models and same conditions (humidity/strains) have many.

So back to the point. Recently I read an article where it stated that over 90F begins to decrease carbon filter performance. Does anyone have experience with this? Being that my air gets pulled through the reflectors, heating the air to 110 F +, then through the fans, THEN through the filters, could this be the cause of inadequate carbon filter performance?

So if I were to arrange it like

Air Flow>>>>Carbon Filter>>>>>>Reflector>>>>>>>>Fan

that would then allow 78 F air (room temperature) instead of the current 110 F in my current configuration.

I am asking this and not trying it myself, because to test this in theory myself would involve A. loss of 90% odor control for a time period. B. It would involve considerable work and expense without knowing if any improvement will be had.

Anyone noticed a difference with the carbon filter on intake end vs exhaust end when your air is vented THROUGH your reflectors?

Thanks in advance

 

[stoneybud2]

Interesting. I know dust humidity will kill a filter. But heat is new to me.
If one could "cook" the carbon hot enough he could clean it to reuse it.
But from my memory. Without a kiln it's impossible to achieve.

I build my own filters. So I may it may not beable to help you.
I have pushed and pulled on thing I find pushing trough a filter is you need an intake filter to stop all dust lint anything. Gotta remember there's no prefilter inside. So any dust particles your jamming in there and into the back of your prefilter.

Second any pinhole down the line before your filter will allow smell doesn't take much.
But that being said if your hood leaks then pulling will cause your grief too.
Something to keep in mind. But all n all I've found it better to pull then push.
SB2

 

[qupee]

How certain are you that there isn't a leak letting your fan push air out before it goes through the carbon filter?

 

[Iffy]

Hi Folks,
I don't get why people add the light reflector into the exhaust equation. I have found a separate cooling system for the lights is beneficial as it draws cool air from outside the room. I use a sealed system so the light cooling air is just exhausted and never comes into contact with the grow room air, so no smell. For exhausting heat I use a super-silent 6" fan & a 6" drawing air through a reversible carbon filter. When I set up my growroom I tried a dual system but the split system I have now, easily outperforms the previous. Both in terms of cooling the lights and eliminating odour from my exhaust.
Stay safe & happy growing

 

[MIway]

you need negative air pressure in the grow area, to capture the odor molecules before the can spread to other areas. well sealed area with lots of negative air pressure & a controlled air intake source. if you can do that, then you have a good chance at a no odor grow.

still need to balance the odor volume to scrubber/fan size, plus rh... but it all comes down to air flows, clean vs dirty air.

it certainly can be done, but not as simple as buy a filter & good to go.

 

[420ish]

when i ran my room like you are with the filter last ,i always had smell problems.you probably have a leak or leaks in your line.i switched to filter fan light then exhaust.no more smell problem.when you run filter then fan with the fan attached to filter any leaks downstream are cleaned air.when the filter is last if you have any leaks at all the smell escapes.

 

[FRANKIE1579]

Hey folks, thanks for the replies. I will be moving all the filters to the other end of the ducting. I am pretty sure there are no leaks, however if other people can use carbon filters 100% effectively then I am doing something wrong and this is the only damn thing I can think of because all other conditions are perfect.

Does anybody knowledgeable in the science in this particular field know if heat impacts carbon filter performance? Am having a very hard time finding any information on google

 

[progre55ive]

Does anybody knowledgeable in the science in this particular field know if heat impacts carbon filter performance?

Canfilters FAQ section doesn't provide the science behind the degrees, only the recommended maximum temperature, which they claim is 80°C / 176°F. It also states that reaching 70% humidity begins to diminish the life of the filter by means of water molecules filling the pore structures of the carbon.

 

[Cannabean]

im winding down so I didnt read the entire thread and i apologise for that but thought I'd add to the discussion that I use the following setup with absolutely no odor issues when replacing the carbon filters every 2 years.

8" diameter 24" long carbon filter>>duct>>1kw light>>duct>>1kw light>>duct>>747cfm 8" vortex fan>>duct>outside

i set it up this way just from reading about others opinions on pushing through a carbon filter vs. pulling through one. not sure what's scientifically correct, but thats what I do. my system is muffled by the 12'+ duct line running from the fan to outside wall port. the duct length just muffles the air noise.

 

[Granger2]

http://www.phreshfilter.com/faq.aspx

Frankie,
Phresh verifies that temps and humidity affect life. They don't say anything about performance. I think you are right, based on your experience and that of others including myself. I've used Mountain Airs, and now Phresh filters and have always had great odor control. I can walk into my room any time and am not greeted with smell. That ends when I open the stalls. After closing them back up, it takes about 5 minutes for the smell to go away.

Sealed room with wood frame stalls that are basically tents. The rest of the room [outside the stalls] is a lung room w/carbon filter running 24/7. Each stall exhausts thru a filter, and into the lung room. The hottest air that goes thru the filters is maybe 85F. Humidity is kept no higher than 70% [rare] and most of the time 50%ish. No smell.

The lamps are cooled with another 6" fan that draws in outside air, thru the lamps, out to attic.

Switching things around will fix you up I'll bet. Report back and let us know if it fixed your problem. Good luck. -granger

 

[Peton]

I think as someone said above, that you might have a leakage. High temps should not make the filter less effective, at least not in a small range of temperature change.
But temperature does increase the amount of vapors from the plants, and maybe that increase overwhelm the capacity of the filter.