Very Interesting High Temps Solution.

[faithlessxxx]

So now that summer is here, both my fellow farmer and I have seen our temps go through the roof. We shouldn't be even trying during the summer, but we both thought, wtf, lets try anyway.

So our temps shot up to about 35C. We've both got massive fans etc, he has a cooltube, I chopped off the room halfway up with a sheet of polythylene, but we realized that the problem is that if the air going in is warm already, you're screwed.

We started philosophizing about different ways to cool things. Computer processors, motorbike motors, lots of other things are cooled by having a fan blow over cold metal.
We thought that if we could think of a construction whereby the intake has to pass over a fair sized amount of metal, it should cool it.

Then I went home. Sat there thinking that glass should be just as bad a conductor of heat as metal, so I fitted an old stormlight cooltube that I had lying around to the intake, shut the door, left it alone for 20 mins, then checked again. The temps dropped 3c.

I was really surprised at the difference it made. This idea could be developed further, I'm sure.

Thoughts?

faithlessxxx Reviewed by faithlessxxx on 06-15-2007. Very Interesting High Temps Solution. So now that summer is here, both my fellow farmer and I have seen our temps go through the roof. We shouldn't be even trying during the summer, but we both thought, wtf, lets try anyway. So our temps shot up to about 35C. We've both got massive fans etc, he has a cooltube, I chopped off the room halfway up with a sheet of polythylene, but we realized that the problem is that if the air going in is warm already, you're screwed. We started philosophizing about different ways to cool things. Rating: 5

[khronik]

heat sinks only work to dissipate heat into a cooler environment. If the environment is the same temperature as the metal, nothing changes temperature.

You're pretty much stuck with either air conditioning, or if the air in your area is very dry, you might be able to cool it by evaporating water somehow.

[Al B. Fuct]

khronik is spot on, well said.

Be careful about the difference between a human feeling cooler and actually reducing air temperature. People feel cooler in the breeze from a fan because there's water evaporating from the skin- not because the air is any cooler due to the air motion. Fans actually add heat to air by way of their motors.

Same for heatsinks or other chunks of metal. Your skin surface is about ~80-85F. When you touch something which has good heat conductivity and the ambient air temp is cooler than your skin, what you're touching feels cool- to you- but it is actually no cooler than the ambient air temp.

[Tomthehippie]

yea great bit of info there both well said! my temps are also way to high! And i donâ??t want to invest in a air-con unit just yet.

You can buy air cooling units that u can fill up with ice every few hours that then blow ice cooled air in to your room.

I had an idea of maybe some kind of water cooled system but i havenâ??t got much further with its design than just thinking about it.

[Al B. Fuct]

Tom, I've seen those ice-cooled heat exchanger units. A grow op of any decent size would eat a 5kg (10lb) bag of ice in very short order and the temperature isn't at all controllable.

These ice devices are only slightly better than evaporative or "swamp" coolers, which are of little to no use in a grow op as they dump lots of humidity into the air and lower temps only a few degrees.

Consideration #1 in a grow op is the ability to ventilate the space to get rid of waste heat from lighting, humidity transpired from the plants and to draw in fresh CO2 laden air.

If you can't ventilate a space adequately, you will always be dissatisfied with the quality and quantity of buds you pull out of it.

[4x5]

how about an old heater core and an old magnet pump filled with glycol alcohol, don't forget the squirrel cage fan.

[Al B. Fuct]

4x5, good onya for thinking about the problem, but a liquid cooling system won't make things any cooler than the ambient air.

The only common device which will remove heat from air is a typical air conditioner unit, though Peltier-effect (PE) cooling devices are kinda interesting. Very expensive, but mechanically mucho simpler than gas compression and evaporation air conditioning, not to mention just plain interesting. PE devices work like turbocharged heatsinks, but still require a place to dump their heat.

[Tomthehippie]

Arse. iv decided to have my lights on at night un till i get aircon.

[Markass]

what about window units? I've seen some of the smaller ones for under $100..I'm actually considering getting one for future grows to aid in cooling and dehumidification

[stinkyattic]

A bit about heat... it is moved in 3 ways: Radiation, convection, conduction. Radiation is what causes the heat burns on your leaves. Convection is why it is warmer near the top of your room... and why you should put the active exhaust up there to take advantage of that. The last is what you are thinking of utilizing... sorta...

but we realized that the problem is that if the air going in is warm already, you're screwed.

Right, which is the reason to use an ACTIVE intake and draw pre-cooled air from a cold place such as a basement of a room with ac.

Computer processors, motorbike motors, lots of other things are cooled by having a fan blow over cold metal.

Actually this is not how it works... the fan blows over HOT metal. The heat sink thing is securely fastened to the item to be cooled (heat is conducted into it) and the many small flanges on it create a greater surface area to be air-cooled, helped along by a fan.

We thought that if we could think of a construction whereby the intake has to pass over a fair sized amount of metal, it should cool it.

This will simply heat the metal. If you are passing air over very CHILLED metal, the heat will come out of the air and warm up the metal, making the air a bit cooler... but this isn't a practical way to cool a room!

Then I went home. Sat there thinking that glass should be just as bad a conductor of heat as metal,

No, metal is a fabulous conductor of heat. Glass, not nearly so much. Glass is actually a pretty decent insulator. When you are running an air cooled hood, the heat is primarily passing through the glass as radiation.

You just need to add an ac to your op and play with bringing very cold air into your room, allowing it to be heated or whatever, and then exhausting it OUT of the house entirely.