Heat stress? heat issues. Help needed.

G.Grizzly

G.Grizzly

Member
Hey,

I have a grow tent. 48'' by 48'' by 72''.

A 600watt HPS bulb with reflector. (Ballast of course)

An exhaust fan at the top of the tent sucking the air out. Another hole at the top of the tent for fresh air to get in.

A fan hanging in front to the light/reflector to cool the bulb, and a oscillating fan at the bottom to keep the air moving around.

My problem here is that my grow room temp is around: 95f to 102f....

I am aware I want my room to be around 80f ideally. Clearly my room it way to hot and my plant is showing signs of heat stress. The leaves are turning yellow and wilting.

I have an A/C In my window about 4 feet away from the grow tent. When I open the tent doors and have the A/C blowing into the tent the temp only drops from 102 to 95.

So even with all the fans, A/C etc. my room still wont drop below 95f. What am i doing wrong/what can I do to help my poor baby?

Thanks,

Grizzly :leaf:
 
*smokey*

*smokey*

Active Member
Have the hole that allows air in at the bottom of the tent mate, alows better cirulation of cooler air. also where is the hot air going to? If its back in to the room where your drawing the air in from then thats the problem. Hope this helps

P.s. Im running a similar system atm and with the hot weather im struggling to keep mine down too. I try running the light at night when its cooler if i can.
 
Little Tommy

Little Tommy

Well-Known Member
If your hood is not set up for air cooled use that is the problem. This is 1 solution. Get an air cooled hood and pull air from the tent, through the hood and out the tent. Ideally you would want to remove that air completely from the room where your tent is. This will involve some kind of ducting and a can type fan. Open passive ports near the bottom of the tent to bring in cooler air from the floor level and exhaust out a port at the top.
 
rocpilefsj

rocpilefsj

Misguided Angel
Sounds like you are sucking in the hot air you are exhausting into/from the same room. Also move the intake to the bottom instead of the top as you are probably just sucking the fresh air out before it is even getting to your plants! The fan will help cirulate the fresh air.
 
Airwave

Airwave

Well-Known Member
G.Grizzly said:
Hey,

I have a grow tent. 48'' by 48'' by 72''.

A 600watt HPS bulb with reflector. (Ballast of course)

An exhaust fan at the top of the tent sucking the air out. Another hole at the top of the tent for fresh air to get in.

A fan hanging in front to the light/reflector to cool the bulb, and a oscillating fan at the bottom to keep the air moving around.

My problem here is that my grow room temp is around: 95f to 102f....

I am aware I want my room to be around 80f ideally. Clearly my room it way to hot and my plant is showing signs of heat stress. The leaves are turning yellow and wilting.

I have an A/C In my window about 4 feet away from the grow tent. When I open the tent doors and have the A/C blowing into the tent the temp only drops from 102 to 95.

So even with all the fans, A/C etc. my room still wont drop below 95f. What am i doing wrong/what can I do to help my poor baby?

Thanks,

Grizzly :leaf:
Click to expand...
You need an air cooled hood, either a cool tube or some other kind. No, there is no way around it.
 
woodsmaneh!

woodsmaneh!

Well-Known Member
Smokey got it. ^^^^^^^^^

First you need to pull air in from the lowest point you can. Hot air rises and cool air sinks.

Vent your hot air anywhere but back into your room with the tent.

If you have room for a pail of small cooler, fill it 1/2 to 3/4 with water add some salt, coarse salt is better, like softer salt and then freeze some plastic pop bottles toss in the cooler repeat as necessary.

You have 96 cf so you need a fan that will produce 140cfpm to replace the air in your tent every minute 140 allows for 6 feet of corrugated flex pipe, if you add any 45 or 90 add another 30% for each one. What's your fan rated for?
 
G.Grizzly

G.Grizzly

Member
Air cooled tube with exhaust out the tent.

Intake from the bottom not the top. Close up the top hole subsequently.

Good advice, It will cost a bit more but I will try it out.
 
G.Grizzly

G.Grizzly

Member
woodsmaneh! said:
Smokey got it. ^^^^^^^^^

First you need to pull air in from the lowest point you can. Hot air rises and cool air sinks.

Vent your hot air anywhere but back into your room with the tent.

If you have room for a pail of small cooler, fill it 1/2 to 3/4 with water add some salt, coarse salt is better, like softer salt and then freeze some plastic pop bottles toss in the cooler repeat as necessary.

You have 96 cf so you need a fan that will produce 140cfpm to replace the air in your tent every minute 140 allows for 6 feet of corrugated flex pipe, if you add any 45 or 90 add another 30% for each one. What's your fan rated for?
Click to expand...
I don't know what my current fan is rated for, it's not much though. I will be picking up a 140cfpm fan to exhaust the air from the cool tube to outside the tent.

Do I need a second fan for intake, or is having a hole at the bottom of the the tent open enough?
 
woodsmaneh!

woodsmaneh!

Well-Known Member
I would skip the cool tube for now and just put the exhaust fan in with an opening or 2 in the bottom. If it works out you saved some cash on the tube. I have a shed full of 8" and 6" cool tubes, along with light movers and some other hoods ext. Fact of the matter is heat is what you want to get rid off not keep, feel a cool tube and it is warm, holds heat, anything that holds heat is bad, I use a gull wing made from aluminum aloe that does not hold heat. You see whan you have something that holds heat you need to work harder to cool it and the air around it.

First Law of Thermodynamics

The first law of thermodynamics is the application of the conservation of energy principle to heat and thermodynamic processes:

The first law makes use of the key concepts of internal energy, heat, and system work. It is used extensively in the discussion of heat engines. The standard unit for all these quantities would be the joule, although they are sometimes expressed in calories or BTU.
It is typical for chemistry texts to write the first law as ΔU=Q+W. It is the same law, of course - the thermodynamic expression of the conservation of energy principle. It is just that W is defined as the work done on the system instead of work done by the system. In the context of physics, the common scenario is one of adding heat to a volume of gas and using the expansion of that gas to do work, as in the pushing down of a piston in an internal combustion engine. In the context of chemical reactions and process, it may be more common to deal with situations where work is done on the system rather than by it.
 
cary schellie

cary schellie

Active Member
cary schellie

cary schellie

Active Member
woodsmaneh! said:
I would skip the cool tube for now and just put the exhaust fan in with an opening or 2 in the bottom. If it works out you saved some cash on the tube. I have a shed full of 8" and 6" cool tubes, along with light movers and some other hoods ext. Fact of the matter is heat is what you want to get rid off not keep, feel a cool tube and it is warm, holds heat, anything that holds heat is bad, I use a gull wing made from aluminum aloe that does not hold heat. You see whan you have something that holds heat you need to work harder to cool it and the air around it.

First Law of Thermodynamics

The first law of thermodynamics is the application of the conservation of energy principle to heat and thermodynamic processes:

The first law makes use of the key concepts of internal energy, heat, and system work. It is used extensively in the discussion of heat engines. The standard unit for all these quantities would be the joule, although they are sometimes expressed in calories or BTU.
It is typical for chemistry texts to write the first law as ΔU=Q+W. It is the same law, of course - the thermodynamic expression of the conservation of energy principle. It is just that W is defined as the work done on the system instead of work done by the system. In the context of physics, the common scenario is one of adding heat to a volume of gas and using the expansion of that gas to do work, as in the pushing down of a piston in an internal combustion engine. In the context of chemical reactions and process, it may be more common to deal with situations where work is done on the system rather than by it.[/QUOTE


















yo grover, i must be a dumb ass none of that makes sense to me, ill take those cool tubes off ur hands they work awsome]
Click to expand...
 
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