How to Remove Heat?

[m3d1c1n3man]

There is too much heat in the grow room! 90+ F ! How to remove?

There is a 400w HID in a room about 4' by 6'. The light is about 2 feet from the plant and yet temps at the bottom of the plant still show 90F. There is an outtake fan a couple feet above the light and a passive intake, otherwise the room is basically sealed, with outside temps around 70F. You can feel the heat coming out of the exhaust. There is also a fan blowing directly on top of the plant and around the HID light. Can't seem to get rid of this heat! What is the usual solution? I know a lot of people use HID's and solve the heat problem so what is the secret? I tried searching the site but does not seem to be working. I thought about putting some ice cubes in there but that seems half-ass. Any help?

 

[billy4479]

Increase you exhaust fan . I like the 8 inch from active air good price 720 cfm a minute . or buy a air conditioner .

 

[Doer]

You think about this correctly. Heat is a substance to be transported out.

You say exhaust fan, but what size?

My secret in a small, hall bathroom is not one secret. HID, even water cooled 1000w, like mine still dump 20% as infrared. So, that has to be managed. 80% is ballasted by 100 gals on the North side of my house, and a 1/6 hp sump pump to drive it. And it is a bit of plumbing problem and 110v relay and a no flow no go, switch is necessary.

It it very very simple. if you have 70 degree air available you could get 80 degree exhaust air.

So, you need a big exhaust fan in CFM,. 170 cfm minimum on a 3x3 ft tent. And I have that and 2, 400 cfm axial exhausts fans also. 3 fans exhaust my space.

So, maybe you are a victim of that old saw about replacing the air 3 x per hour?

That is for mim. CO2. For heat management, you need that every minute, I think.

Also, consider re-radiation. IR energy is absorb by ALL the mass, including and especially the dry wall.

So, I cover everything...everything with mylar bubble wrap.

My tent
water barrel
all walls
hot box collector for the A/C unit
ceiling
electrical wire junctions and power strips are all shaded and isolated by mylar or white Panda plastic sheets.

So, helps?

 

[m3d1c1n3man]

Thanks Doer, that's a lot of good information and some things I didn't consider.

I don't know the actual CFM of the fan but it is about 4 in wide, blowing through a 4 in duct. I can feel it blowing pretty good even several feet away from the end of the duct. I'm sure it's plenty for CO2 exchange but perhaps more is required for the heat as you mentioned. Though any stronger of a fan and it's going to seem like an extreme blow rate for the little room!

Anyways... I'm just amazed at how much heat this 400w puts out! If times really get bad I can use it as a space heater in the wintertime. I was using CFL's before this and they put off practically no heat.

has anyone tried maybe say taking a bucket of water and freezing it, then putting it somewhere in the grow room until it melts, and repeat? I wonder what kind of results that would generate?

 

[Doer]

Thanks Doer, that's a lot of good information and some things I didn't consider.

I don't know the actual CFM of the fan but it is about 4 in wide, blowing through a 4 in duct. I can feel it blowing pretty good even several feet away from the end of the duct. I'm sure it's plenty for CO2 exchange but perhaps more is required for the heat as you mentioned. Though any stronger of a fan and it's going to seem like an extreme blow rate for the little room!

Anyways... I'm just amazed at how much heat this 400w puts out! If times really get bad I can use it as a space heater in the wintertime. I was using CFL's before this and they put off practically no heat.

has anyone tried maybe say taking a bucket of water and freezing it, then putting it somewhere in the grow room until it melts, and repeat? I wonder what kind of results that would generate?

Wait, just checking. You are exhausting the room, correct, not trying to pressurize and heat it by packing air in?

Your exhaust need to be 3x the intake and it needs to change once a minute minimum.

Hey "going to seem like an extreme blow rate " has no meaning to me. Sorry. Just guessing has no place.

You said you wanted help with heat. That's the main help.

 

[Doer]

Cooling is an entirely different issue. And I would say since you are balking at the main concept, you will have no grasp of the lack of efficiency of using an ice bucket and air ice interface.

Let me just ask. Where does the heat go? Into the ice. Where does the water go from melt? Into the bucket.

Where now is the heat? In the bucket, in the room. No heat transport out.

 

[m3d1c1n3man]

I believe the idea would be to remove the bucket from the room once the water has melted i.e. heat transport out. Technically it's no different than venting air, it's just water exchange instead of air exchange. It would probably take a lot of cold water to work and so be impractical, but the physics is sound.

 

[Doer]

Well, it is impractical, and there are better ways.

You get what is called an icebox. The idea is to not let the water ice system stall, which it will. The water begin to ballast the temperature pull down, sooner than you think.

The idea is that you circulate chilled water, thru a heat exchange, and fan inside the room, but the water/ice reservoir is outside your room and well insulated.

That is because, the amount of ice needed and the temp/energy curves are just not worth it, if you just allow ice to just melt in water. But with a tiny pump recuiculating the cold water, works fine, lasts a long time.

Around a $100. Then get a little plumping going in a picnic cooler full of ice water,the bigger the better.

http://www.hydrogalaxy.com/growing-lights/lighting-accessories/6-ice-box-heat-exchanger/?gclid=COWB3_vJgb0CFYdFMgodzGQAQg

 

[Ou8aCracker2]

There is too much heat in the grow room! 90+ F ! How to remove?

There is a 400w HID in a room about 4' by 6'. The light is about 2 feet from the plant and yet temps at the bottom of the plant still show 90F. There is an outtake fan a couple feet above the light and a passive intake, otherwise the room is basically sealed, with outside temps around 70F. You can feel the heat coming out of the exhaust. There is also a fan blowing directly on top of the plant and around the HID light. Can't seem to get rid of this heat! What is the usual solution? I know a lot of people use HID's and solve the heat problem so what is the secret? I tried searching the site but does not seem to be working. I thought about putting some ice cubes in there but that seems half-ass. Any help?

Going by the part of your post I highlighted in bold...you're exhausting back into the same room you're pulling fresh air from aren't you?

That's a no no.Route the exhaust into the attic,another room,or through a window via a window exhaust box that can be built cheaply.

Also,you failed to mention the size,airflow rating,and type of fan (inline centrifugal,squirrel cage blower,duct booster,etc.).

 

[Ou8aCracker2]

You think about this correctly. Heat is a substance to be transported out.

You say exhaust fan, but what size?

My secret in a small, hall bathroom is not one secret. HID, even water cooled 1000w, like mine still dump 20% as infrared. So, that has to be managed. 80% is ballasted by 100 gals on the North side of my house, and a 1/6 hp sump pump to drive it. And it is a bit of plumbing problem and 110v relay and a no flow no go, switch is necessary.

It it very very simple. if you have 70 degree air available you could get 80 degree exhaust air.

So, you need a big exhaust fan in CFM,. 170 cfm minimum on a 3x3 ft tent. And I have that and 2, 400 cfm axial exhausts fans also. 3 fans exhaust my space.

So, maybe you are a victim of that old saw about replacing the air 3 x per hour?

That is for mim. CO2. For heat management, you need that every minute, I think.

Also, consider re-radiation. IR energy is absorb by ALL the mass, including and especially the dry wall.

So, I cover everything...everything with mylar bubble wrap.

My tent
water barrel
all walls
hot box collector for the A/C unit
ceiling
electrical wire junctions and power strips are all shaded and isolated by mylar or white Panda plastic sheets.

So, helps?

A 4" 170cfm inline centrifugal will only give a lights on tdiff of 10°F above ambient when using a 600w light,but the thing is that would have to be 170cfm of effective airflow.After attaching that 170cfm inline fan to ducting,effective airflow is reduced due to pressure losses from connecting ducting.And every bend in the ducting reduces the effective airflow/adds to more pressure losses,and attaching a carbon filter reduces effective airflow by atleastb25% again adding to more pressure losses.

Read ventilation 101 before answering.

OP,exhaust to the attic,to another room,or out a window via a window exhaust box.Also a 6" 440cfm inline centrifugal (can fan,eco plus,elicient,hurricane,sunleaves,vortex) to make up for all pressure losses and effectively cool the light and ventilate your grow space.

 

[Ou8aCracker2]

I am addressing you.You. an't simply say a 4" 170cfm inline centrifugal is going to properly cool a 600w grow without taking into consideration the ambient temps and pressure losses...PERIOD!

By the way,good job at acting like an adult.

 

[Ou8aCracker2]

170cfm for a 3x3 tent.

Sure looks like you didn't take wattage if lighting,ambient temp,and pressure losses into account to me bub.

Smoke a bowl,it's good for the soul because obviously your's is filled with negativity.

 

[Ou8aCracker2]

Dabs,I don't smoke flowers.

 

[Doer]

See? I wish you were more high.

 

[Ou8aCracker2]

Here take a dab on me lol

 

[Doer]

Ah blimey. Or whatever. Lingo me shivers.

Dabs is it? Marvelous clarity. Color brings the reminder of Summers to come while the Stand is Firm and appears quite Resilient. And I must say the in situ Pose is classic

 

[dajosh42069]

It got pretty petty in here really quick.
Quite frankly, outside observer... Doer, you just flew off the handle in no time at all.
Perhaps the 2 of you should find a way to agree on the correct way to cool a room, as it's not rocket science....
I just wanted to see how others were handling their heat issues, and instead I, and everyone else, are treated to an argument.

 

[Ou8aCracker2]

Dajosh,ventilation 101 holds all the answers to you questions about ventilation and cooling.

I apologize for derailing the thread,but had to make my point.

 

[dajosh42069]

Naw, I feel you. You at least seemed willing to argue your point, rather then just be the one yelling the loudest.
And I'm already reading your Vent 101 guide. Very detailed and interesting. A little more info then i'm capable of using, but def helps to have the illustrations to translate for the lay persons.

 

[Doer]

It got pretty petty in here really quick.
Quite frankly, outside observer... Doer, you just flew off the handle in no time at all.
Perhaps the 2 of you should find a way to agree on the correct way to cool a room, as it's not rocket science....
I just wanted to see how others were handling their heat issues, and instead I, and everyone else, are treated to an argument.

Hey no one called for your judgement. No one has to agree here. No one values your toss off solutions to nothing.

And I believe, if you are paying attention in life you simply mind your own business..