Air Cooled Hood Info

[Tetra]

Hey guys room size 11x6x8. I am going to be running two 600 Watt lights with air cooled reflectors I live in northern Canada and usually only grow in the winter so I believe I can make this work. I'm gonna be picking up two SolisTek 1000 Watt ballast that have the ability to use 600 Watt bulbs aswell. Down the road I plan on using A/C when Ive got the cash for a mini split. My question is will 6 inch reflector hoods be sufficient for two 600 Watt lights? Also will 6 inch air cooled hoods be sufficient for two 1000 Watt lights with A/C installed?

 

[GT21]

Hey guys room size 11x6x8. I am going to be running two 600 Watt lights with air cooled reflectors I live in northern Canada and usually only grow in the winter so I believe I can make this work. I'm gonna be picking up two SolisTek 1000 Watt ballast that have the ability to use 600 Watt bulbs aswell. Down the road I plan on using A/C when Ive got the cash for a mini split. My question is will 6 inch reflector hoods be sufficient for two 600 Watt lights? Also will 6 inch air cooled hoods be sufficient for two 1000 Watt lights with A/C installed?

You can do it without the ac... i do and i run them in summer.
Run your lights at night and get a 400 cfm blower for each 1k hood. Pump the air into the space from the bottom and dump the air into the next room.

 

[Tetra]

You can do it without the ac... i do and i run them in summer.
Run your lights at night and get a 400 cfm blower for each 1k hood. Pump the air into the space from the bottom and dump the air into the next room.

G21 what size is your room and I'm guessing 8 inch hoods right? Also have you incorporated your carbon filter into the air cooled hoods as well oflr is that stand alone to?

 

[GT21]

G21 what size is your room and I'm guessing 8 inch hoods right? Also have you incorporated your carbon filter into the air cooled hoods as well oflr is that stand alone to?

6in hoods....2....5x5x7 tents ya its best to Put the air through the filter... i dont really use air cooled hoods much though

 

[Tetra]

my lights will run in line though? ive been a little confused on what im going to run to cool this room. The total volume of the room is 560 feet squared. What size fan should i consider?

 

[Tetra]

think ill go two 600 watt 6 inch all inline with carbon filter.

 

[GT21]

think ill go two 600 watt 6 inch all inline with carbon filter.

Its all about air exchange... ac not needed

 

[Grumb Blotto]

Not sure if this will help but i run 6 1000 watts in epic 8" air cooled hoods. I myself wouldnt go to a 6" hood unless i had a seperate fan for each one. I have 3 in a row on each bank and use a 3 speed 8" max pro and it keeps the hoods at about 77 degrees acording to the laser temp. But i also draw cold air in from an unheated room to run through the hoods. I also have an air conditionr in now, but before i did it was way to hot. I was getting temps in the 90's for the air temp in the room. Oh and my room is 8' x 15' x 8'

 

[Tetra]

I'm wondering if I'd be more efficient if I ran 8 inch on 2 in line lights rather than 6 inch. Would you guys recommend I cool the lights independently or add the carbon filter on the line?

 

[Grumb Blotto]

I'm wondering if I'd be more efficient if I ran 8 inch on 2 in line lights rather than 6 inch. Would you guys recommend I cool the lights independently or add the carbon filter on the line?

You can go wither way. Just keep in mind if you have the filter on the same line as one of cooling lines for the hood that you will have restrictions from the filter and wont pushas much air, and also if you are sucking the air from your grow room through your filter and then iut throughth the hood that it will not cool as good because you are using the warmer air from in the room to cool the hood. But it shouldnt be to bad if you are running 600

 

[Tetra]

I think I'll get into closed loop cooling if I ever use c02 but for now I think I'm going to use a carbon filter on the line.... I think lol ughh I over think things way to much.

 

[We Solidarity]

Winter in Canada sounds cold, any reason you don't run the hoods open and cool w/ outside air? Less headache, more weed.

 

[DANKSY]

the solis-tek 1000 watt ballast will run a 600 bulb but it will shorten the life of the bulb. they also say they dont have any spectral shift when you dim the ballast with a 1000 watt bulb... i dont think i am completely sold on that yet.

 

[Papa Indica]

I'm running just one 600 in a 4 x 4 tent and I have my carbon filter ducted to my light with ducting out the other side to my fan, keeping the fan the last thing in line so that it's pulling air through the system, these fans pull air much better than they push it. I don't pull any outside air or dump it outside, my fan points right at the open door of my room, as long as the house temps and rh stay under control so do my tents.

 

[Tetra]

Winter in Canada sounds cold, any reason you don't run the hoods open and cool w/ outside air? Less headache, more weed.

Yeah It can and Im pretty close to Northwest Territories I've seen it get minus 56 degrees Celsius here (thats almost minus 70 degrees for my American friends). I don't want to run air that cold over my bulbs I'd rather regulate the room via natural gas heater and take the air from inside the room.

 

[Grumb Blotto]

Yeah smart idea Tetra, air that cold would probably explode your bulbs or at least do something horrible to them. My room is not sealed, and i have temp under control. It really comes down to air exchange. If you can remove the hit air from the hoods faster then they build it up, you wont generate heat issues from there. And then you would have another fan attached to a carbon filter pulling air from in your case i would assume an interior room. If i understand you are running 600w in a closed hood with 6" ports. Figure each hood is what about 3 x 2 x 2 or so. So say 15 cf to be safe. Plus your ducting lets say you have to wind up using 10' of it so that would be another 5 cf. So 20cf total. If you get a fan rated 240 cfm you could change the air on two hoods 6 times every minute. Thats new cool air every 7.5 seconds. You have lots of options. You could go smaller fans and do each separately or go bigger and do banks of lights. The same process is used to find out the correct fan for the room also. Just keep in mind that one will have resistance from the filter. Hope this helps.

 

[rmoltis]

I have my carbon filter ducted to my light with ducting out the other side to my fan, keeping the fan the last thing in line so that it's pulling air through the system, these fans pull air much better than they push it. I don't pull any outside air or dump it outside

Just a little advice I posted this elsewhere.
I see many people placing their fans at the end of their exhaust which is slightly less advantageous.
Heres why

The reason the can fan should be after the charcoal filter but before the light fixture.

The fan drawing air through the charcoal filter.
Will create negative pressure in the chamber space. Ensuring that all air gets drawn through the charcoal filter for scrubbing.

Ahead of the fan it creates positive pressure through the air cooled light fixture then ducting into the room.

This does 3 things.

1.) It creates a higher mass of air flowing over the bulb since its positive pressure (more air density). This means the air will have a higher heat capacity.
Combined with the pressure of the air acting on the bulb to aid in heat transfer.
As well as being a denser charge of air
It will carry out more heat.

2.) If anything after the fan (lighting fixture/ducting) has air leaks. The already scrubbed air would leak back into the chamber to be re-filtered through the charcoal filter.

3.) The fan will be exposed to lower temperatures being before the light increasing its life expectancy.


If placed after the light fixture or at the end of the exhaust stream. It would work opposite to all 3 of those variables.

1.) The negative pressure would create a lower mass flow of air (lower density).
It would be lower pressure meaning lower heat capacity.
It would transfer less heat from the bulb due to lower force of air pressing onto the bulb.
And also due to a lower density of air flowing through.
All this would reduce the efficiency of drawing the heat outside.

2.) If there are any ducting leaks before the fan and after the charcoal filter(ducting/light fixture).
The negative pressure created by the fan will draw unfiltered air (bypassing the charcoal filter) out of the chamber and into the room. Leading to your neighbors finding out.

3.) The can-fan will be exposed to higher temperatures reducing its life expectancy.

 

[Ooopsi]

1.) It creates a higher mass of air flowing over the bulb since its positive pressure (more air density). This means the air will have a higher heat capacity.

Pressure and heat capacity. Never heard that before. Hmmm... Guess I'll be trying out sth new over the weekend... Thanks man! Good to know!!!

 

[rmoltis]

Just a little advice I posted this elsewhere.

I see many people placing their fans at the end of their exhaust which is slightly less advantageous.

Heres why


The reason the can fan should be after the charcoal filter but before the light fixture.


The fan drawing air through the charcoal filter.

Will create negative pressure in the chamber space. Ensuring that all air gets drawn through the charcoal filter for scrubbing.


Ahead of the fan it creates positive pressure through the air cooled light fixture then ducting into the room.


This does 3 things.


1.) It creates a higher mass of air flowing over the bulb since its positive pressure (more air density). This means the air will have a higher heat capacity.

Combined with the pressure of the air acting on the bulb to aid in heat transfer.

As well as being a denser charge of air

It will carry out more heat.


2.) If anything after the fan (lighting fixture/ducting) has air leaks. The already scrubbed air would leak back into the chamber to be re-filtered through the charcoal filter.


3.) The fan will be exposed to lower temperatures being before the light increasing its life expectancy.



If placed after the light fixture or at the end of the exhaust stream. It would work opposite to all 3 of those variables.


1.) The negative pressure would create a lower mass flow of air (lower density).

It would be lower pressure meaning lower heat capacity.

It would transfer less heat from the bulb due to lower force of air pressing onto the bulb.

And also due to a lower density of air flowing through.

All this would reduce the efficiency of drawing the heat outside.


2.) If there are any ducting leaks before the fan and after the charcoal filter(ducting/light fixture).

The negative pressure created by the fan will draw unfiltered air (bypassing the charcoal filter) out of the chamber and into the room. Leading to your neighbors finding out.


3.) The can-fan will be exposed to higher temperatures reducing its life expectancy.

Pressure and heat capacity. Never heard that before. Hmmm... Guess I'll be trying out sth new over the weekend... Thanks man! Good to know!!!

Science!!

This is airs specific heat capacity vs pressure

General rule of thumb. when you put a gas or fluid under pressure it increases the amount of heat it can hold (specific heat capacity).

Say that same gas or fluid under pressure is then vented into a lower pressure environment.
It would have a lower ability to hold heat.
Which means it would dump all its excess heat it can't hold.

Kind of similar to how air temperature corresponds to how much moisture can be held in the air

A good example is an air conditioner.
Gas is compressed into a fluid and absorbs heat from the hot side (outside usually). This is a reason a/c units lose efficacy at lower outdoor temperatures. It also gets warmed up being compressed.
Then it travels into an expansion chamber where it loses its pressure, turns into a gas then sheds all heat. causing a rapid cooling effect. Mainly due to having a now lower heat capacity Until recompressed again.
This then cooled gas runs through the radiator fins with a fan blowing over it to transfer the cold


Pressure of said gas or fluid when it is higher it usually creates a higher thermal conductivity interaction between the surfaces it interacts with.



Higher pressure= higher thermal conductivity.
Meaning it transfers heat between the air and surface more effectively.

Lower pressure= lower thermal conductivity.
Meaning less effective heat transfer between the air and surface.

You could relate this to lightly touching a warm/hot surface and not getting burned.
Vs.
Pressing very hard against said surface getting burned quicker.

 

[basseye]

Just a little advice I posted this elsewhere.
I see many people placing their fans at the end of their exhaust which is slightly less advantageous.
Heres why

The reason the can fan should be after the charcoal filter but before the light fixture.

The fan drawing air through the charcoal filter.
Will create negative pressure in the chamber space. Ensuring that all air gets drawn through the charcoal filter for scrubbing.

Ahead of the fan it creates positive pressure through the air cooled light fixture then ducting into the room.

This does 3 things.

1.) It creates a higher mass of air flowing over the bulb since its positive pressure (more air density). This means the air will have a higher heat capacity.
Combined with the pressure of the air acting on the bulb to aid in heat transfer.
As well as being a denser charge of air
It will carry out more heat.

2.) If anything after the fan (lighting fixture/ducting) has air leaks. The already scrubbed air would leak back into the chamber to be re-filtered through the charcoal filter.

3.) The fan will be exposed to lower temperatures being before the light increasing its life expectancy.


If placed after the light fixture or at the end of the exhaust stream. It would work opposite to all 3 of those variables.

1.) The negative pressure would create a lower mass flow of air (lower density).
It would be lower pressure meaning lower heat capacity.
It would transfer less heat from the bulb due to lower force of air pressing onto the bulb.
And also due to a lower density of air flowing through.
All this would reduce the efficiency of drawing the heat outside.

2.) If there are any ducting leaks before the fan and after the charcoal filter(ducting/light fixture).
The negative pressure created by the fan will draw unfiltered air (bypassing the charcoal filter) out of the chamber and into the room. Leading to your neighbors finding out.

3.) The can-fan will be exposed to higher temperatures reducing its life expectancy.

This is the first time i ever read a good reason to push air past the lights rather than pulling air .and everything you posted makes sense,nice.thanks.