Hi. I use electric dampers. When is too cold thermostat close vent damper and open second damper. Now air goes throw carbon, fan, cool tube and back to my space. In the grow box I have got small eletroc oil heater. When is hot vent damper open and second damper close. Air goes throw carbon, filter cool tube and outsite.
Heating intake air
- Thread starter bravedave
- Start date
bravedave
Well-Known Member
Of course, my room itself is insulated with R19 on the walls and ceiling and every crack is caulked inside and out. So I believe I can keep the heat in easily enough. It IS the adding of CO2 air and the smell removal without too much heat loss that is the goal. The unheated building my room resides in is 40'x60' so we are talking a rather large undertaking and it will not happen this winter.
Cool and I think similar to what jiji was suggesting. I like my filter/hurricane fan/PVC exhaust but it is not subject to much tweaking without an overhaul I am hoping not to do quite yet. Here is what I am thinking:
I have an older analog GE timer that allows me to "tab" down to every 15 minutes over 24 hours. I am thinking I will add a damper of some sort on my intake...if a "chincy" mechanical one opens automatically when the exhaust kicks in, it can work. Currently, with the exhaust on, the intake fan(although off) spins like it is on so I know I have some decent pressure. I then will either position my current oil-filled/radiator heater directly in front of the intake so when the damper is open the cold air at least hits the heater first before dispersing or I have another small hot-coil heater I could either place similarly in front of the intake or possibly in my filter box on the outside...and it would get turned on the same time the exhaust kicks in via that GE timer I describe.
So the question then again becomes...how much CO2 replenishment is necessary. Would a 15 minutes exhausting every 2 hours or so be enough for this small room??? 15 minutes I think certainly replaces the room air.
GrowerGoneWild
Well-Known Member
You should be able to supplement the heat of the room with a co2 burner, I have an older propane co2 burner that uses a pilot light so it does put off some heat and adds to the RH. A pilot light puts out around 600 to 1000 BTU. A 1500W heater puts out around 5000BTU.
So it seems to me that a C02 burner with the pilot on idle should work, it would reduce your venting problem, and since cold air has low RH that would work. My only problem is in full flower when RH rises and you're adding RH with the co2 burner.
I currently exhaust 3 times the volume of my grow room, during my 2 venting cycles. it does drop the temps, but I try to time it when the lights are on, so I can utilize the waste heat. I'm still recording my temps but i'll have more data when I go to the garden. I think I would model my vent times around this to minimize temp drops.
GrowerGoneWild
Well-Known Member
As far as Co2 in concerned, I would have to use a PPM monitor. I've been manually calculating on times for my burner for co2 addition only. I think I was accurate. I need to calculate the addition of c02 from a pilot light.
ProHuman
Well-Known Member
That depends on the fan, and how many cubic feet per minute you can exhaust.
Plenty of CO2 in the air if you do the math, and set up the times accordingly.
jijiandfarmgang
Well-Known Member
I don't think this will work to well. When its below zero, you would suck in too much air even on a timer, and you will get a basically a humidity bomb. Or possibly shock your plants, negating any C02 improvement. On a 4k sealed room below -10 (mini split no longer worked) I tried using a crappy 6 inch duct booster running constantly lights on and mechanical damper. It cooled the room, but introduced too much humidity around the fan (sweating everywhere).
You might get something to work using heaters, but you could potentially spend more on electricity than a C02 gen or at least close.
Figure out temp and humidity, C02 will be fine.
- Jiji
bravedave
Well-Known Member
Will look into a burner...may want to try a less expensive approach first. Let me know if you have a model suggestion.
Yeah, I have done the math on air replacement but this is a bit different as I am going from constant air replacement and thus a pretty constant level of C02...to where I need to determine how long a room full of air/C02 will last before it needs replacing.
So the fan with the humidity problem was your makeshift exhaust? The air coming in isn't going to be that humid I would not think. If its not snowing and its not melting it is generally pretty dry. I may look into some sort of CO2 system but not for this year. You're right though, my timer will not work unless I could heat that air as 15 minutes is a long time in that cold. We will hit the 30s this weekend so some testing can be done.
Thanks all
GrowerGoneWild
Well-Known Member
I found my burner for cheap I only spent 40 bucks.. I like it because it has a pilot light that runs constantly. Green Air products cd-3-LP. It is discontinued tho. Its a little small for my grow tho... but I run a ventless propane heater that has a pilot so that works good for me. Nowadays they are either water cooled or electronic ignition.. kinda works against us trying to utilize waste heat.
jijiandfarmgang
Well-Known Member
It isn't. But the cold air has less water saturation value. What it touches will condensate. You will see.
- Jiji
Jussblaz3420
Well-Known Member
Can you pull the cold air from outside thru ur hood into the room? The heat from the bulb may be enough to keep it warm, unless its bad for the bulb or could potentially crack it maybe idk, and u could get another 600w or something and gull wing it to give off more heat
jijiandfarmgang
Well-Known Member
No, you'll get a pool of condensation on the reflector and hose will drip condensation.
The best way (probably) to set it up would be with a heat recovery ventilation system. Never heard of anyone trying that in a grow room though.........so yeah........
- Jiji
bravedave
Well-Known Member
Ahhh, ok. Well hopefully I can avoid it. I was skeptical about my Amish Redneck filter box. I wondered whether the air would have much of a chance to cool (when it was loaded with ice) as it was getting sucked through the HEPA straight into the room. It did. Pretty fun to watch the temperature click down when I threw the ice in. Although skeptical about this too I am optimistic that a space heater in that same box will heat the air just enough so it does not totally warp my room temps while hopefully at the same time it is burning up some of the humidity. It needs to run at the same time as the venting period, of course and this could be accomplished.
bravedave
Well-Known Member
Thanks. I am trying to avoid disconnecting anything.
bravedave
Well-Known Member
You are right...it is not big enough for your grow. I will give you $35 for it.
It looks like it is made to hang from the ceiling too. I have just the place.
GrowerGoneWild
Well-Known Member
Hahahahah... . I'm totally laughing my balls off..You are right...it is not big enough for your grow. I will give you $35 for it.
I bought mine off ebay.. so i looked for ya.. Might be a natural gas model, I think you can convert to propane tho.. gotta check the manuals tho.
I have a link to somebody that has a bigger one however, they are trying to scalp you on the shipping price 230$ to ship?.. WTF?.. Mebby its just to where i'm at...?.
http://www.ebay.com/itm/GREEN-AIR-PRODUCTS-MODEL-CD-36-CARBON-DIOXIDE-GENERATOR-D312-/181542903713?pt=US_Hydroponics&hash=item2a44ccdfa1#shpCntId
Jussblaz3420
Well-Known Member
Just throw one of those plug in space heaters right infront of where ur intake comes in, problem solved.
GrowerGoneWild
Well-Known Member
Heaters are usually shut off during the lights on cycle, venting is best when temps are high.
bravedave
Well-Known Member
A little update...
So far, with exhaust plugged into my GE, 96 tab, timer...with my oil- filled, electric, heater positioned in front of passive intake and plugged into a LUX thermostat outlet set on 73F...with the temps in the barn running from 37 to 55...I have pretty easily managed to keep things between 68 and 78F. Managing mainly by varying the exhausting/venting running times. Heater is seldom on with the 600 watter providing all necessary heat. Exhaust/venting is on about 40% of the time keeping things from getting too warm...so the CO2 should be fine. These temps are nothing compared to whats coming though. Actually, "winter is coming".
GrowerGoneWild
Well-Known Member
I hear ya, i'm already down to the low 30's high 20's, (outside) and I'm still been working on sealing up the building, and I'm working on a subfloor. My heater does not need to run during the lights on cycle, and ive been having long vent times because I put it back on a temp trigger. So the lights are doing a great job of heating the building. Ive pretty much removed the forced vent time now that I have a dehuey. However the air is so dry, I'm getting very low RH, 16%- 30%. But I only have a few plants right now because of construction.
After my subfloor insulation project is finished, (1 1/2 foam) I'll switch on the co2 burner pile a bunch of plants in.. This should help me with RH and heat.
As far as the passive intake of cool air, I pretty much sealed up my door, except the lower part, I have a light curtain in front of that, so that controls the draft, so it kinda acts like a damper, when the exhaust fan kicks on, its enough to move the curtain and pull in cool air.
Good to hear from ya and your solution.. winter is close by for me too. and I've been busy getting things right for the winter.