Keepin Cab Temps Down?

[Chronic777]

With summertime coming soon, any tips for keeping the temp of your cab down?

I already got good exaughst & intake fans, but im still hitting 29c already, in june/july this is gonna get serious!

Is my only option having my intake coming from outside? (so buy some longer ducting)
Im also gonna get adjustawings that come with a heat sheild/super spreader

 

[Justin_Credible]

Hey Chronic,
I know that the most efficient way of cooling for me is air in (from outside) and air out. I do have to run ac sometimes during the summer, but only during the day when the lights are off. I get lucky with the temps at night being enough to cool my room when the lights are on. Sometimes during the summer I have to shut down my air in because it is so hot. But if you are saying you are at 29 c now...that is almost what 80-85f? You may want to use the air in at night if temps are low enough to cool the room your fine. But then during the day (in summer months) with temps your are saying you have now, you might want to shut down air in and (if you have the room in your cab) use a small portable ac. I hope that I was of some help here for you.

 

[Chronic777]

Thanks for the advice, i'm gonna extend my ducting so i got air direct from outside, luckily my room is in the shade so i might be okay with the super spreader heat sheild aswell... no room for an ac unit in my tent thats for sure!

Oh yeah, and im gonna have it so the lights are on at night time & off during the day
Thinking to have the lights on at 9pm til 9am

 

[ThaMagnificent]

yea AC would be your best bet!

 

[Chronic777]

My tents pretty small so no ac unit can fit in there, plus its like £200 for an ac unit, way too expensive for me right now

Im hoping i can squeeze this grow in before it gets too hot and the heat shield combined with intaking from outside will be good enough, using the heat sheild during winter my cab temp dropped a good 5c, i get a nice cool breeze at night so i reckon i might just about be alright as long as only have the lights on at nightime, if i have to hit 30c ocassionally, so be it...

 

[cork144]

how olds the bulb? old bulbs kick out more heat compared to a newer one,

see if theres any DIY light diffusers on the DIY thingy

 

[Chronic777]

Nice, ill def invest in a new bulb then, was just gonna use the one from my last grow...

Cheers mate

FREEDOM!

 

[NicholasSmokes]

Not the answer you are looking for most likely, but my solution is to time my crops so that I take a break from mid-June thru August. Gives me more time to enjoy the summer weather, no HID heating up my apartment, no plants to care for when I go on vacation, and no tent to worry about cooling.

 

[Maj.PotHead]

Ventilation 101

http://www.icmag.com/ic/showthread.php?t=112862

 

[Chronic777]

I got very good intake & extract, i got 2x 173m3/h fans, the ducting on the intake naturally slows the intake slightly so i get negative pressure, i got tons of airflow in a less than 1x1m tent

It actually doesn't make sense apart from that the light kicks out serious heat

 

[funkervogt]

I run my flower chamber at night. It sits in my office.

During the summer, I open the windows over night to let in the cool night air (~60-65 degrees). My newest cab runs about 7-10 degrees over room temp. It seems like simply opening the window will eliminate the need to add an AC or whatever. Night time is the right time.

 

[Justin_Credible]

how olds the bulb? old bulbs kick out more heat compared to a newer one,

see if theres any DIY light diffusers on the DIY thingy

Absolutely true! And might I add, older bulbs also put out less lumens.

 

[simon]

I run my flower chamber at night. It sits in my office.

During the summer, I open the windows over night to let in the cool night air (~60-65 degrees). My newest cab runs about 7-10 degrees over room temp. It seems like simply opening the window will eliminate the need to add an AC or whatever. Night time is the right time.

Good advice. My rooms run at night, as well. Even though daytime temps can be high, at night the air is much more cool. Windows open, the cabs runs at 1-2F above ambient with a 600HPS', at ambient with a 400, and the main room (4x600HPS) slightly higher.

Simon

 

[medi-useA-Redux]

Have you thought about a portable tent refrigerated ac?...would fit into most cabs easily...

muA

 

[The Mud Shark]

sealed and vented reflector worked for me. It dropped temps about 10' F, from 90+ to consistently under 82 with lights on.

 

[hoosierdaddy]

If you only have one duct in for fresh air, try running another one in. It may surprise you.
And I agree that a cool tube makes a considerable difference in temp.

 

[cannavore]

There is some very good advice here. I notice you mention a/c is not a possibility. That being said, the last two people who recommended an aircooled reflector are right on point. If you are in an already warm climate and not supplying a/c and growing in a small confined space (cab) you will need an aircooled hood.

Hoosier also brought up another good point about supplying more intake.

With an aircooled hood and adequate intake/exhaust a space or cab fitted with anywhere up to 50+ and more wpf should be able to maintain within a few degree of ambient without the addition of a/c.

Negative pressure is a good thing to contain smell, though too much negative pressure could be detrimental if it starts to become a nuisance in regard to sufficient intake. Negative pressure is negative pressure, but more than the slightest negative pressure starts to choke out the fan and affect performance. This is not a problem if a fan is oversized for the task. All of this can be factored in to help determine the best solution for your heat problem.

Those that mentioned running at night gave a great piece of advice. Use the climate to your benefit if at all possible. If you are not running a/c and the climate is warm, you will need to have the intake and ventilation at it's peak and an air cooled reflector. Small enclosed spaces heat up quick my friend.

I may have missed it, what is the size of the space and lighting in the cab? General figures would suffice. A 250 watt lamp could get away without a air cooled reflector possibly if other variables are favorable, but much more would be difficult to achieve. Also higher temperatures (up to high 80's) are not the end of the world, but you will fair well to grow higher heat tolerant strains if this is the case. Sativas in general is a good place to start looking for a heat tolerant genome. Good luck with your cab, may it bring you many flowers.

 

[BLUNToPOTomuss]

Im not sure how much 173m3/h is...... but at 3x3x6 (just a guess height) is 54 cuft. Ive always used a minimum of 3x exchange for AIR EXCHANGE ONLY and shoot for upwards of 7-10x exchange if you add in heat removal.

Im runnng a 2x2x4 cab= 16cuft, Im running a 256 CFM blower to exhaust and scrubb. even if I loose 30% power through my scubber and 3 ft duct run Im still sitting at approx. 10x a minute.

So does 173/m3h= upwards of 8x exchange of your cab? If not get up to that number and the heat issue will more than likely stay 8-10 degrees above ambient IMO

Good Luck!

 

[gdbud]

173 M3/h = 102 cfm which sounds low to me if he is running it through a scrubber.

 

[gdbud]

I got very good intake & extract, i got 2x 173m3/h fans, the ducting on the intake naturally slows the intake slightly so i get negative pressure,

I would use both fans for exhaust one for the light and one for the tent, and increase the number or size intake duct.