Grow Room Design & Setup
Grow room fan question for temperature control and dark cycle use in the
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I've been running a 10 inch outlet fan and filter and an 8 inch intake fan to control ...
Grow room fan question for temperature control and dark cycle use
I've been running a 10 inch outlet fan and filter and an 8 inch intake fan to control odor and temps in my bloom room. They are hooked into a splitter which is plugged into a CAP controller which turns them on when temps get above 75 in the room. Here is my dilemma. During the dark period I want the fans to kick on every so often (maybe once an hour for a few minutes) to clear the stagnant air from the room, reducing smell buildup and relieving moisture heavy air that increases the growth of powdery mildew and mold. The plants naturally breathing and perspiring builds up a lot of 'wet' air while the lights are off for 12 hours.
The problem is, during the winter the room stays very cool during the dark period and the fans will not turn on from the CAP controller. I want to find a way to leave my fans plugged into the temp sensor to operate as normal during daytime, but turn on once an hour for a brief time during the dark period without having to unplug the fans every dark cycle from the temp controller and plug them into a timer. I want the fans to be automated still, but switch to a temperature independent timer during the dark automatically rather than unplugging them myself. Anyone know how I could set up this duality to work? Has anyone figured out a good solution to a similar problem?
With some controllers you can set idle speeds.
If the CAP controller you have has this you could set idle speed to something like 15% that way they would always run at that speed unless temps increased.
meybe add a 2nd fan,much smaller on a timer? I have run a PC fan 24/7 on a room to keep some air moving while using a bigger fan on a thermostat to control temps
Last edited by mrmadcow; 01-21-2012 at 11:49 AM.
Where are we going & what am I doing in a handbasket?
I'll Have to browse the catalogs and look for a controller with an idle speed setting, that would probably work pretty well. The CAP controllers I've seen don't have that, so I'll widen my net. Thanks for the idea, had no idea there was such a thing!
Originally Posted by jondamon
Good idea madcow, I've got an old 8 inch booster fan laying around. I could throw it on a timer and run it every so often in the dark. The only thing that worries me is probably needing to tie into a filter still because venting without a carbon scrubber is gonna stink up the whole block. And if I do that I'm gonna need an electronic dampener on a T or Y vent (so I can close it when the other fan runs, they would have to share the same in and out ducts as my primary fans) and another inline fan (at least a decent fan, cheap ones don't pull through a filter usually in my experience). When you ran your PC fan did you use a filter? Did you have it in a room or a tent?
Originally Posted by mrmadcow
Yea having a second fan means all kinds of trouble of needing a second filter. I was trying to think of a solution for my own room and finally decided I would just run a dehumidifer in the room at night. unfortunately thats alot of power being used to clear the humidity, and thats also alot of room being used by the dehumidifer considering the small size of my room. But it seems the easiest way to control night time humidity. What is the CAP controller you are talking about Arcadia? my flower room is getting away with no forced venting for now becuase the plants are small and only burning small lights on them, but I need to get this all sorted pretty soon as I'll be putting in more lights for flower
actually having a small fan with a small filter might be the best way to go now that I think of it. Unless there is a device that can run the big fan at a very low idle(if there is something that can do this please show me it, it sounds perfect for what I'm doing). Having a fan run at all times means you always have negative pressure, and any air escaping is being filtered. If you simply turn off all your fans and run a dehumidifier there will no longer be negative pressure and minute air leaks could cause some stink, If you have really smelly plants or lots of plants.
I wish I knew more about electricty... I thought of a cool way to work the fans but I'm not sure if this is safe or if it would work: If you split the power line that runs your fan and had one line go through a timer(or humidistat) and the other line go through a thermostat and then merged the two lines together just before the fan then the fan would run any time either the thermostat or the humidistat were to switch on. But I don't know exactly how you would do that or if it is safe to do.
Heres how I would do that: have an extention cord with 2 plug ins on it. Plug a thermostat into one plugin, and a humidistat into the other. Create a custom extention cord that has 1 female and 2 male ends(this is why its dangerious because if one male becomes unplugged it could electrocute you or short circuit on any conductive material). Plug one of the males into the humidisat and the other male into the thermostat. plug the fan into the female. Mr mad cow you're in the electrician thread alot maybe you can clarify whether or not that will burn down the house lol.
I have a similar setup, fan-wise and controller. Those are large fans, I assume you have a large room? I have done it both ways withs a dehumidifier and a heater. I think the heater is cheaper. I use the radiant heater kind on a timer so it runs only at night with a fan blowing at it away from plants, that's why you need some extra room so it's not near the plants. The heat will help raise dew-point/lower relative humidity as well as make your exhaust come on.
Another alternative is to set your night temp so low that it will never be acheived. Then run your lights through a timer that is on for 12 hours(the daytime) and then flip every other peg for the other 12 hours. During the daylight time your fans will run as normal. During the night your fans will come on for 15 then off for 15 all night long.
Lately though I have just been running the intake and exhaust fans all night.
Good luck grower.
I have to find a solution because my intake temperature is 50 degrees so I cant have that coming in all night long or my plants will not be happy. The heater idea is pretty good, a bit expensive though because to heat my 4x6 room takes 1500watts! Its a cold basement
I hear you man, winter's a bitch! So is Summer.
Originally Posted by Thedillestpickle
On a side note, I use the heat from my lights to heat my house all night long so this helps offset the heating when lights off. Of course this is only possible for certain applications.
I had that same problem..... I dont know how much DIY skills you have or maybe you might know someone but my pops built me a sweet computer proccessor control panal to solve the same type of problem ... Theres is no timers it runs like your computer would on an enternal clock... If the Power were to go out then come back on everything resumes as normal nothing needs to be reset, no timers need to be adjusted for the period power was out.... It has 8 120v outputs connected to 8 different sockets that i can cut power on/off as i wish controlled by the Computer.
This way i just tell the Computer when to turn the fans,lights,ac,heater,dehumidifer and Co2 On/Off and at what times of the cycle to do it.....
Only thing i cant do which is a bummer is change the rpm of the Inline fans im using....Im still using Speed Controllers on all fans i just make sure i plug my speed fan controller into its designated corresponding Socket controlled by the Proccessor....
If you know an electrician or maybe hire one its well worth it if you plan to go long term.... espicailly if your going to go closed loop system in the future
DONT HATE , APPRECIATE !!