Fan size/ carbon cannister size for 8x8 room w/ 2 1000 MH lights; need cooling HELP!

I have been searching all over here; and have not really been able to find the answers I need- I have an 8'x8'x8' grow room w/ 2 1000 watt lights in Sunlight Systems YieldMaster Classic II reflectors w/ 6" intake/ exhaust duct connectors. I will be sucking air from outside the room, running through 6" ducting. I will also be splitting at a Y inside the room to exhaust a limited amount of inside air after sucking through a carbon filter can (I have a tank style CO2 system that will be running in the room)...What size Dayton style blower/ Hydro Farm Active air (CFM) do I need to go with, and what size filter can???

HELP!

Anyone out there who knows how to figure out this shit??? Or where I can find out? For example, how many CFM will it take to cool a 1000 Watt Metal Halide in a SunLight Systems reflector w/ 6" duct connectors? Any references here on RollitUp?

When I do a search here on the subject, I have been sifting through tons of blah blah blah posts which are supposed to be discussing system requirements, but say a whole lot of nothing...

Ok....I am in the same boat as you except my room is a little bigger with 1 vented hood (1000 watts) and 1 400 watt air without a vented hood. My room is 6 feet high and 8 feet wide and about 12 feet long. My vented hood has a 6 inch ducting on it for cooling. I was thinking I will get a inline fan but is there one with enough capacity to turn over enough air in my room without needing another vent. I was thinking I can suck through the carbon filter then through the hood then is the fan inline going into the attic to vent. Then haveing a fresh air intake from under the house where its nice and cool.

How big of a inline fan to get?

Grasshopper

Did you get your fan figured out? What calculator did you use?

Found it. Halfway down this post is listed the air exchange formula.

OK guys so this come's up as or in a thread just about every other day....
with this formula a room would be able to get in the 70-72 deg range even when it's 100+ but yet still maintain humidity at night time with proper air movement

Calculating Heat Load
Heat is measured in either BTU or Kilowatts. 1KW is equivalent to 3500BTUs.
The heat load depends on a number of factor's

1.The floor area of the room
2.The heat generated by equipment
3 the heat from lighting
4.The number of room occupants
5.The ambient temp ( your room's starting temp ) this will be added asap im still playing with the #'s

1.Floor Area of Room

Room Area BTU = L x W x 40 ( H = 8foot + 5btu per foot after that)

If you have a wall that is facing the sun add in for the extra heat

Sun facing wall BTU = L x H x 40

2.Equipment
This is trickier to calculate than you might think. The wattage on equipment is the maximum power consumption rating, the actual power consumed may be less. However it is safer to overestimate the wattage than underestimate it.

Equipment BTU = Total wattage for equipment x 3.5

Ballast in room BTU = ballast wattage/2 x 3.5

3.Lighting

Lighting BTU = Total wattage for all lighting x 4

Air cooled hood BTU = wattage x 4 / 2
@
400= 200-250 cfm
600= 250-300 cfm
1k = 300-350 cfm
^ is just a guide cfm per hood will be on your ducting/SP....

4.Occupants
even being that im only there for 2 or so of the 12 hrs i like it to be able to handle the extra sweat when i smoke one.

Total Occupant BTU = Number of occupants x 400

Total Cooling Required

Add all the BTUs together.

Total Heat Load = Room Area BTU + Total Occupant BTU + Equipment BTU + Lighting BTU

If your using a portable a/c

Total Heat Load BTU x 2

^this has been from threads on this site i dont have any real experince with portable a/c's other then one and it was not in a growroom but if you plan on getting one id think about one thats bigger then you thought about


sample

so if we have a 3 x 3 room with 1k and 200 watt's in fan's/pump's

for room we need 360 btu
for fan we need 700 btu
1k = 4000btu
ballast in the room = 1500 btu

we would need a/c that is 6560 btu i would round up to the next size 7kbtu


air exchange
aka intake/exhaust
complete air exchange every 4-5 minutes is average for a grow room/greenhouse (co2 control)....
for heat control (no a/c) i like to use 2.5 minutes {1M is best imo}
m=air exchange in min's

l x w x h = cf / m = cfm

lets use are room from above as a sample
3 x 3 x 8 = 72 /2.5 = 28.8 (30)
highend turn over = 72cfm
lowend turn over = 30cfm
now for the light 1k = 300-350cfm

exhaust system and air-cooled hood should be separated but most ppl cant/dont ( it's spendy) so add them together if your using 1 fan for both

the fan size we need is 330-422 remember you have duct loss (SP) in the sample room i would use a 440 cfm fan

SEER & EER ratings NO they are not the same.....

EER, or the Energy Efficient Ratio, is a measure of how efficiently a cooling system will operate when the outdoor temperature is at a specific level - usually 95°F. EER is calculated as a simple ratio of BTU's to the amount of power a unit consumes in watts. Here is an example using an air conditioner with 12,000 BTU's and consuming 1500 watts of power:

EER = BTU's / Watts

12,000 / 1500 = 8

EER = 8


While it is true that the higher the EER and BTU's, the more efficient the cooling system, many make the mistake of purchasing oversized air conditioners and ignoring EER ratings. The following is an example of an air conditioner with 12,000 BTU's and 1200 watts:

12,000 / 1200 = 10

EER =10

This would mean that this second unit can produce the same amount of cooling but more energy efficiently. Therefore, to save money on your monthly electric bill, choose a cooling system by getting an appropriately sized unit with a high EER.


SEER(seasonal energy efficiency ratio) measures how efficiently a residential central cooling system (air conditioner or heat pump) will operate over an entire cooling season, as opposed to a single outdoor temperature. As with EER, a higher SEER reflects a more efficient cooling system. SEER is calculated based on the total amount of cooling (in Btu) the system will provide over the entire season divided by the total number of watt-hours it will consume:

SEER = seasonal Btu of cooling / seasonal watt-hours used

Cool, thanks, +1 for you! I used a formula originally for just air exchange; which is 150 CFM which, is enough for one 1000 watter- and circulation, but not enough for two 1000 watters AND suck through a carbon canister...Right now I got the 150 CFM Dayton hooked up just to cool the room; but I cant run my CO2 yet as a result...However, my baby clones just rooted last week, so no sweat there as all I need is the 1000 watter for them as they are not at the 'stinky stage' quite yet...I kust ordered a Hydro Farm 465 Active Air (brand) squirrel cage fan from Horticulture Source
http://www.horticulturesource.com/product_info.php?products_id=6394
online; best deal I could find, at only $87.96 (bargain, as far as I'm concerned) for such a high output fan. Just in case it is too much air, I'm going to get a 3speed fan control switch for it. Right now just the little 150 cfm Dayton, which is venting out the basement window makes so much fucking noise it is audible from one odf my neighbors side yard which is closest to the window... So w/ the 465 cfm blower I decided to tap ito the furnace chimney in my house after the backdraft damper in the system so the noise isnt' so obvious... I figure 465 CFM should do the trick... Thanks for the formula!

Woops! Accidental double post.

Right on .....good find on the squirl cage. They are pretty loud to I hear.

hopper

I reccomend 200 + CFMs per light. The carbon filter is whats dicking ya. Go for a seperate fan and can filter and of course (1) 440 cfm for those 2 MH.
If you had 8" hoods you could get a 720 CFM fan to get the job done....
I wouldn't make an equation out of it..........

And why are you exhausting the room with tank style c02?

[FONT=Verdana,Arial,Helvetica] [FONT=Verdana,Arial,Helvetica] Dan's Method
Calculating By Room Volume [/FONT][/FONT][FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]You will find many calculations on the web for sizing a fan for ventilating indoor gardens; however, what many of these calculations fail to take into consideration is the friction loss on carbon filters and increased temperatures from HID lights. So here's my calculation method which you can use as a guide for sizing an exhaust fan for a growing area (keep in mind that this calculation will give you the lowest required CFM (Cubic feet of air per minute) required to ventilate the indoor garden.) [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]Step 1: Room Volume
First the volume of the room needs to be calculated. To calculate multiply length x width x height of growing area e.g. A room that is 8' x 8' x 8' will have a volume of 512 cubic feet. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]Step 2: CFM Required
Your extraction fan should be able to adequately exchange the air in an indoor garden once every three minutes. Therefore, 512 cubic feet / 3 minutes = 171 CFM. This will be the absolute minimum CFM for exchanging the air in an indoor garden. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]Step 3: Additional factors
Unfortunately, the minimum CFM needed to ventilate a indoor garden is never quite that simple. Once the grower has calculated the minimum CFM required for their indoor garden the following additional factors need to be considered: [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]Number of HID lights � add 5% per air cooled light or 10-15% per non-air cooled light. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]CO2: add 5% for rooms with CO2 enrichment [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]Filters: if a carbon filter is to be used with the exhaust system then add 20% [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]Ambient temperature: for hot climates (such as Southern California) add 25%, for hot and humid climates (such as Florida) add up to 40%. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]An Example
In our 8' x 8' room we have 2 x 1000w air cooled lights, and we plan to use a carbon filter. We also plan to use CO2 in this room. The ambient temperature is 90 �F (32�C), however, we will be using air from another room that is air-conditioned. Here's the minimum required CFM to ventilate room: [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]1) Calculate the CFM required for room (see above.) [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]2) Add 10% (for 2 air cooled lights.) [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]3) Add 5% of original CFM calculation (For CO2.) [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]4) Add 20% of original CFM calculation for Carbon Filter. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]5) Air is coming from air-conditioned room so no need to add any other percentages. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]6) CFM = (171 CFM) + (171CFM x 10%) + (171 CFM x 5%) + (171CFM x 20%) + ( 0 )= 231 CFM. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]This is the absolute minimum CFM required to ventilate your room. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]The next step might seem to match the closest fan to this CFM. However, for this example I'd choose a six inch fan with a CFM of around 400 or more, and a 6 inch carbon filter to match. The extra CFMs may seem a bit excessive (calculations on most indoor gardening websites would recommend a 4" fan and a 4" carbon filter) but it's always better to over-spec since we need to compensate for air resistance in ducting too. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]Also, as we are using a carbon filter we will need to match the fan with the filter so that the fan that will neatly fit onto the filter. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]If all the variables are kept the same and we changed the room size from 8' x 8' to a 12' x 12' then the minimum required CFM would be 519 CFM. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]The All-Important Inflow! [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]An intake port can be anything from a gap under the door to an open window - even a hole in the wall. The best place for an intake port is diagonally opposite from your exhaust fan; that way, air has to pass across the entire room - very efficient. You can put a piece of screen over the opening to keep insects and animals out, a piece of A/C filter to keep dust out, or a louvered shutter or backdraft damper that opens when the fan turns on and closes when it turns off. You can also use a motorized damper. This gets installed in-line with your ducting and is plugged into whatever device controls your exhaust fan. When your fan turns on, it allows air to pass. When your fan shuts off, it seals completely, preventing CO2, air, etc. from passing. You can get creative with these devices and use one fan to control two rooms, etc. [/FONT][/FONT]
[FONT=Verdana,Arial,Helvetica][FONT=Verdana,Arial,Helvetica]One additional note about intake ports - you will see much better results from your exhaust system if you install a second fan to create an active (as opposed to passive) intake system. Normally, when your exhaust fan sucks air out of your room, air is passively going to get sucked back into the room. By installing a second fan on the intake side, you will reduce the amount of negative pressure created in the indoor garden, thereby cutting down greatly on the amount of work the exhaust fan has to do and allowing much more air to pass through. If you're not sure or you don't want to spend the money, start out with just an exhaust fan. If it's not performing as well as you thought it would, try adding an intake fan - you'll smile when you see the difference! [/FONT][/FONT]