Controlling Temps during Transitional Seasons with Large Temp Fluctuations

[guy incognito]

How the hell do you guys control your environment during the transitional seasons? The temps here got to mid 80's yesterday, then down to 64* last night, back up into the 80's today, then it's gonna dive down and only have a high of 54* tomorrow. I can't run the AC when the temps outside are going below 60*. It seems incredibly wasteful. I also can't keep my temperature in check if the ambient temp get's above 70*. I cannot exhaust air fast enough to keep a reasonable temperature. My grow is upstairs and consists of 2 1,000 watt hps, 1 400 watt hps, and about 150 watt of cfls right now. The hps are all cool tube with a fan running 24/7 pulling air from an outside source and dumping into the attic.

I think I can close the room and have the AC run and cool it during the summer when it's hot. Or I can hook the scrubber to exhaust into the attic and hook that up to my controller when it's not as hot. If im using the AC I need to set the scrubber up to not exhaust and just recirc the air within the room, so it's a mild pain in the ass to switch between the two set ups. This would be fine if I simply had to make the transition from winter set up to summer set up once, but it looks as though I will need the AC during a few evenings in the week, but not the rest of the time. The whole point of getting an environmental controller though is so I don't have to sit there and babysit it.

Any advice? Or should I just plug the AC in and just deal with wasting lots of electricity to maintain the perfect temp?

 

[tafbang]

just have a fan blowing the heat out and blowing at the plant area to blow the hot air out

 

[hornedfrog2000]

Environmental controllers. Something like the sentinel evc-2, etc.

 

[guy incognito]

I already have an environmental controller and an exhaust fan. Once the outside temperature gets above 70* though I cannot remove heat fast enough. I have an 8" centrifugal fan air cooling all my hid lights and a 6" centrifugal fan w/ scrubber pulling air out. Even running 24/7 the temp spikes.

My problem is that it goes from mid summer weather (mid 80's today) with 3 hid lights running on the 2nd floor, and by the end of the weekend it will hit 45*. How do I deal with 40 degree ambient temperature swings that straddle the point where exhaust alone is no longer sufficient and I need AC?

Today I need AC for sure. If it's 85* outside, the 2nd floor with all those lights running will not stay below 100* without AC. But if I hook up the AC and block the room off it's going to just keep running because those lights generate so much heat. When the temp drops to 45* outside, it's still going to be too hot inside my room with all those lights and no air exchange, so the AC will be running then too. At that point I can just exhaust the hot air until it get down to temp. My problem is that I have to manually change the set up of the room between these 2 settings. Either I set up for no air exchange with an AC, OR I don't use AC and just vent the air.

So I either hook the AC to my environmental controller and run it pretty much constantly, even though temperatures are going to be dropping into the 40's.

Or I hook up the exhaust fan and keep a reasonable temperature all the time (except when outside temps go above 70ish, then the heat will build and build until I have 100*+ grow rooms)

Or I spend the time to switch between AC and exhaust every time the ambient temperature crosses the 70* mark.

 

[303]

Why don't you run the lights 'on' cycle at night when its 60 something? Then lights off when its 80 something during the day..? Bottom line you must run your AC off the enviormental controller. Which one are you using and do you use co2?

 

[guy incognito]

Why don't you run the lights 'on' cycle at night when its 60 something? Then lights off when its 80 something during the day..? Bottom line you must run your AC off the enviormental controller. Which one are you using and do you use co2?

I run the lights from about 4pm to 4am. I Could shift it slightly later to coincide with the most optimal temperatures, but I also need to be able to get in there during lights on. Optimum times for me to garden are about 5pm to midnight depending on the day. This way I can work all day, then tend to the garden after work, then leave for the night. I also don't want to change the cycles because im mid grow.

I have the sentinal CHHC-4. No CO2 yet, but i'm going to set it up over the next few weeks. That was the reason I went with CHHC-4 over a much cheaper temperature controller.

Once the CO2 is set up and im dealing with summer temperature the AC will stay hooked up 24/7 and ill do no exhausting.

The easiest option seems to be hook the AC up and forget about it. I really dislike the idea of running the AC when the outside temperatures are dipping below 50* though. Seems very wasteful, and also might arouse suspicion from neighbors. I know i'd be suspicious if my neighbor was running an AC unit and it was below 50* outside.

 

[Buddy Ganga]

Damn man..

There a few questions I have to ask before I can come up with a solution for you.

1. Do you own the home or rent ?
2. Forced air heating ? (duct work)
3. Are you skilled in any way ? (crafty ? missing any fingers from the last saw you touched)
4.What year do you think the house was built?

 

[guy incognito]

Damn man..

There a few questions I have to ask before I can come up with a solution for you.

1. Do you own the home or rent ?
2. Forced air heating ? (duct work)
3. Are you skilled in any way ? (crafty ? missing any fingers from the last saw you touched)

1. own
2. yes forced air heating. A single duct comes from the basement up to the room. It is essentially useless. It doesn't get enough flow through it to heat or cool the room. I plan on disconnecting the duct and using it as a conduit to run water and natural gas up to the room.
3. I am crafty and smart, but not trained to be a handy man. I have to research and figure stuff out as I go.

Also keep in mind that if it's an expensive or convoluted fix, it will probably end up being easier and cheaper to just run the AC. Within a month ill be running the AC 24/7 anyway, so how much am I going to spend running it for the next month while the temperature fluctuates wildly?

 

[303]

1. own
2. yes forced air heating. A single duct comes from the basement up to the room. It is essentially useless. It doesn't get enough flow through it to heat or cool the room. I plan on disconnecting the duct and using it as a conduit to run water and natural gas up to the room.
3. I am crafty and smart, but not trained to be a handy man. I have to research and figure stuff out as I go.

Also keep in mind that if it's an expensive or convoluted fix, it will probably end up being easier and cheaper to just run the AC. Within a month ill be running the AC 24/7 anyway, so how much am I going to spend running it for the next month while the temperature fluctuates wildly?

Not sure where he was going with those questions but in regards to the co2 you ust exhaust it. I have the CAP Air 3 controller and its set to turn co2 on for 15-30mins, then shuts off, then exhausts spent co2. Then on again back to 1500 ppms.. Then again and so fourth, you will need to exhaust the co2. But when your running co2 leave the room temp set to 90 degrees, this would make things more efficient. My plants certainly don't mind the heat, and more beneficial co2 intake when its 85+, or so I've read..

 

[Buddy Ganga]

Problem solved, seriously..

All you really need is 2 4 inch flex ducts.
Run them both down through the duct to your basement.
One to draw air up and the other to exhaust the air.

Then run the exhaust over to your dryer hook up using a "Y" to connect them both so there is no tranistion needed to do laundry.

The only pricey part of the solution will be the fan for the cooler air.
You are going to want to get a 6 or 8 inch blower for cooling using a reducer to attach the 4 inch duct. (expect some awesome air flow)
Then just an inline fan or two for the exhaust..

The more powerful cooling fan will actually help the air flow in the exhaust ducting too.
This will let you use the cooler air from the basement rather then an a/c..


303, not sure if you understand the humidity issues we have to deal with around here.
I've lived here and in Colo and there is a huge difference.
90 here is like 120 there.

 

[303]

Problem solved, seriously..
303, not sure if you understand the humidity issues we have to deal with around here.
I've lived here and in Colo and there is a huge difference.
90 here is like 120 there.

Heard that.. But wouldn't the AC unit dehumidify the air significantly?

 

[Buddy Ganga]

Well that's the problem we face with temps and the humidity in addition to our already humid air due to watering.
The ac will cool the area but will then leave lots of condensation on walls and pots if there isn't plenty of air flow.

Up here our average basement temp's are about 65, and the air exchange itself will remove the excess moisture as it cools.
This will also greatly reduce operating costs.


In the winter I use my grow to warm the house, in the summer I use the house to cool my grow.

 

[guy incognito]

I also have a dehumidifier in the room. I like my basement to stay cold because thats gonna be my summer hang out. I just ordered a tankless water heater and pump to get my co2 set up.

I don't think the basement air would cool it anyway. I put a 20" box fan in the window, then another one several feet in front of that, then a third one in front of that for fresh air intake. I have a 6" centrifugal fan pulling air from all 3 tents, scrubbing it, then dumping it in the attic. Being on the 2nd floor with 2,400 watts of hid plus 150 watts of cfl plus other equipment is just too much. Even with a 6" fan sucking air our, and 3 box fans pushing fresh air into the room I can't remove the heat once it gets close to 70*.

 

[guy incognito]

Also FYI my current electric bill is around $290/mo and I pull about a pound a month from this set up.

 

[Buddy Ganga]

Well, the best I can do is tell you whats working for me right now, and that's what I did.

I'm actually cooling a 1000 watt raptor in a 5x 5 tent connected to my 4x8 with 2 600 watt hoods and then exhausting through the flue in my chimney.
Via the basement and flex ducting with a 440cfm fan.

You might notice that the walls are covered with panda film and I only have a small opening for the window that only opens part way.


That removes the heat issue from the hoods, and the incoming air from the basement helps cool the room itself.

P.s. awesome numbers man, it's nice to read from an actual grower that knows wattage doesn't mean as much as technique/skills/knowledge. Way to many people thinks it's all about how many watts you can hit the plants with.
Kudos!

 

[guy incognito]

I think the air intake for my lights is too hot. I thought 745 cfm running 24/7 would be enough to evacuate that attic and keep it at a reasonable temperature, but I think I may have been mistaken. It must be 20* hotter in the attic than outside. Even hotter on the outlet side, but too hot on the inlet. I think rigging something to the window to get fresh air intake for my lights will help.

 

[dajosh42069]

Dude, i'm dealing with the SAME issues, i've got an exhaust, the grow room door stays open all 12 hours the lights are on, and it's in a standard bedroom, 10x11. Has it's own AC vent in there, ceiling fan, and Osc fan as well. All the heat from the light is being sucked out, but somehow, my temps still reach like 85 unless i'm running the AC every hour. And I know it's summer (at least it is here, with temps above 90 each day) but this is ridiculous!
Ac it'll have to be I suppose!

 

[guy incognito]

I think my attic is too hot. The room is building up with heat because the attic is ungodly hot. The room builds up with more heat because my cool tubes are inefficient because the attic air is so hot.

 

[dajosh42069]

Should be much of an issue unless your intaking from there...

 

[guy incognito]

I intake from one side and exhaust to the other side. I didn't realize that the air would recycle between attics like that. I assumed it would ventilate on both sides keeping my intake at ambient temperatures, and the exhaust side hot. Instead I think the air might be traveling over top of the room to the other side. Either that or my attic is just hot on a day like today, staying about 20* over ambient temperatures. The fan should be removing all the air from the attic on the intake side in 1 or 2 minutes which is why I assumed it would stay pretty close to ambient.