Alright so here's what I got going on... A 7x6x7 room in the basement that has a 8 in' prop fan for outtake (like 500 cfm) thats at the top of the room, along with a small 4 in' intake (like computer fan) at the bottom of the room which is blowing in room temp air. 1000W HPS light about 2 feet above plant height (currently at 12/12 1st week of flowering). 2 oscillating fans below and above canopy. Also recently a container with dry ice was put above the light (2 lbs) that flows over the light. The room is not air tight, there are a few holes near the ceiling here and there. Will the dry ice or CO2 even be an advantage? It is about 86 during daylight and 84 during night time cycles. There has been a heat wave the past 2 weeks so its always like 90+ outside which makes it really hot in the room. There's a dehumidifier so RH is normally between 55-70 depending on whats going on with the plants. Would it be a good idea to run the intake air through a cooler with a piece of dry ice in it? That would make the intake fan blow in both CO2 sublimation from the dry ice as well as cooling the room temp air as it blows through the cooler (sucking in air that passes by a -109 F ice block). Will the air being blow into the room from the cooler be too cold? or too much CO2? Any suggestions or ideas? Once the heat wave passes I still don't think the temp will go down because it gets so damn hot in the room, so I think I need some sort of device (such as the dry ice cooler I mentioned) that will blow in really cold air that will cool off in the heat of the room (hopefully lowering the temp to 75-80) while at the same time blowing in rich CO2 for the plants to use. Let me know what your thinking..Thanks. Some shitty pics until I fix my cam... currently (use your imagination): new idea: Input?
O mate, I can so understand your problem. Here in Autralia, we have similar issues with small indoor grows and HPS bulbs....heat, heat and MORe heat, especially with a giant 1000 watter!!!!! It can be difficult to solve.....one thing that is a fact is it is virtually impossible to get the temps in your room or grow area lower than your outter (or outside) temperatues without the use of air con. Its just a matter of pulling as much air from the grow room as you can....of course this introduces new problems such a light leeking and fan noise.....its a pain in the ass really!!!! You seem to have your head screwed on right tho and im sure you will get the problem solved. I tend to lean towards the more heat resistant strains of MJ myself or at least propogate (or clone...same thing) the plants that dont mind the heat as much. Best of luck!!! -Milsy
If you had a one gallon bottle of water, and you were sucking water out with a one inch hose on one end, and were replacing that water with a water intake using a 1/4" hose, you would run out of water in no time. In order for your 8* fan to work properly, you will need to increase the size of the intake substatially. Your intake doesn't necessarily have to have a fan, as you could make it a 'passive' intake. If you change the intake to passive it should be two to three times the size of the exhaust. However, no matter how efficient your ventilation is, the temp inside will always be warmer than the ambient air you are drawing from. Generally about 10F. as a 1000W light produces 3,000 btu of heat. If you want to use CO2, you are looking at sealing the room (making it airtight) so the CO2 stays in the room. To compensate for the heat, you would require air conditioning. You will be much better off with A/C than dry ice. Dry ice will be very expensive and not very accurate..... keylime
So do I understand that you have a 4" diameter intake hole and a 8" diameter exhaust hole? Rule of thumb is you should have twice the intake area as exhaust area, so your intake is woefully small. Note that a 4" round hole is not half the size of an 8" round hole. The area of a circle is Pi time the radius squared, so a 4" diameter hole has an area of approx 12.6 sq inches and an 8" diameter hole has an area of approx 50.2 sq inches, or about four times bigger. So you need eight 4" diameter holes for intake to match against one 8" diameter exhaust.