New grow room setup plz take a look :-)

[Sparkie]

Hi all

I have just completed a 1.2 m grow tent setup, I have built around the outside a 1.3m timber stud frame to keep in the heat & hopefully smells to, I have a 100mm 4inch intake fan from outside the stud frame to inside the tent, I have a 150mm 6 inch out take fan n carbon filter to above the tent but not outside the stud frame which is also fully ply boarded, I then have another 100mm 4 inch fan from above the tent to the outside world, I also have a 150mm 600w cool shade light wired into a digital central heating/hot water controller for lighting which also controls my last mentioned extract fan, I purchased off eBay a digital heat/cooling controller which is set at 28 degrees, if drops to 27 a 55w tubular heater kicks in, if gets to 29 degrees it kicks in my 1st & 2nd mentioned fans, I also have 4x socket outlets for 24hr power to control my hydroponics water pump,nutrient heater oscillating fan & circulation pump.

My question is fellow growers

Does it sound like I'm heading in the rite direction?
Does it sound like iv been extra clever in the way I have wired & setup my grow room?
Is there anything else I should have or change?

Please give me your feedback on anything you have read

Much respect people

Thank you

 

[4u2sm0ke]

I wouldnt be adding walls to keep heat in...

 

[BackWoodsDrifter]

I be dence as a stump soaked in stream water fur a week pilgrem so ifin yual can at some point post some pics be able to give ya pinion from the bushline Hope yual do well yur trails travlin pilgrem

BWD

 

[Sparkie]

I wouldnt be adding walls to keep heat in...

You would do if ya knew what country I live in pal

 

[The Hemp Goddess]

Are these computer fans? IMO, you are going to need at least one decent centrifuge type fan, to go with that carbon filter. In addition, fans are for more than cooling your space. Your plants need a continual supply of fresh air all the time the lights are on for proper photosynthesis. So at least one fan should be exchanging air all the time you have the lights on. You want negative pressure in your tent--this is what helps keep smells contained and directed to somewhere it doesn't matter or a filter.

I also don't quite understand what is controlling your light?

I think that you are making this a little more complicated than it needs to be.

 

[Sparkie]

Are these computer fans? IMO, you are going to need at least one decent centrifuge type fan, to go with that carbon filter. In addition, fans are for more than cooling your space. Your plants need a continual supply of fresh air all the time the lights are on for proper photosynthesis. So at least one fan should be exchanging air all the time you have the lights on. You want negative pressure in your tent--this is what helps keep smells contained and directed to somewhere it doesn't matter or a filter.

I also don't quite understand what is controlling your light?

I think that you are making this a little more complicated than it needs to be.

All 3 fans are extraction fans , 6 & 4 inch fans would be some massive computer fans, i have created a negative pressure by having a larger 6 inch extraction fan to my 4 inch intake (fresh air fan) my central heating controller is bringing on my lighting system for instant 20hr on & 4hr off!! Simples

 

[Sparkie]

My fans are also kicking in every 4-5 minutes for approx 2 mins everytime for a good exchange of air which keeps my humidity to around 55-60

& carbon filter also in there to,

 

[The Hemp Goddess]

Many computer fans are 4". I still don't really know what you mean by extraction fans. What cfm do they pull? I like to exchange my air a couple of times every minute.

 

[Hushpuppy]

It sounds like you are having to deal with very cold incoming air? If so then I understand you having to ballance heating and cooling your space. Normally most indoor grows are having to deal with building up too much heat and are constantly trying to remove the heat.

I have cold air intake issues that I have to keep up. Like you, I have a room with my grow tents inside so that I can draw air into the room where it can be heated some before being pulled into the grow tents. I also have to ballance that warming with the heat generated by my lights. Its tricky but very doable.

Are your "extraction" fans centrifugal type fans that draw air like a vacuume cleaner blower? or are they just propellor blade fans that have air space around the fan. If they are the prop type then you will want to look into getting the centrifugal fans for dealing with summertime heat as the prop fans don't create vacuume, they only push air. The centrifugal fans are much more efficient at removing heated and depleted air because they pull air rather than pushing it. If you are in a place that doesn't get much in the way of hot summer temps then you may be in good shape like you are.

 

[DrFever]

to much cold coming in will only cause major issues mostly condensation which can lead to mold etc cold fronts hitting warm fronts = perfect storm

 

[Hushpuppy]

I don't have any trouble with it myself. I have small intake holes in the floor of my building and I control how many of them are open to allow x amount of air intake while my exaust fans are pulling the hottest air out of the bldg through my tents and lights. I have found that the winter air typically has less moisture in it even when the humidity is high, so when it comes into my building and warms up with the heated air, its humidity level drops and by the time it gets into my tents it is only about 40%Rh in 70ish degree air.

 

[trillions of atoms]

put up some pics...

 

[DrFever]

I don't have any trouble with it myself. I have small intake holes in the floor of my building and I control how many of them are open to allow x amount of air intake while my exaust fans are pulling the hottest air out of the bldg through my tents and lights. I have found that the winter air typically has less moisture in it even when the humidity is high, so when it comes into my building and warms up with the heated air, its humidity level drops and by the time it gets into my tents it is only about 40%Rh in 70ish degree air.

Are these holes in your floor directly outside air ???? for instance i have a room with two 4" holes on one side of wall and two 4" holes on other end of room, ( Passive air in ) straight outside air if outside temps were 42 below that is what would be coming in the room from one side, other side is 1600 watts of exhaust power.
and what i found is floor and walls from air in side were soaked condensation build up enough as Black mold started growing on cinder blocks and concrete behind the panda film
since building a hot box meaning a thermostatically controlled shed to allow cold air to warm up a little prior to entering room , on my passive side condensation Stopped floors and walls dry problem solved
doesn't matter if out side RH is low once cold and hot meet there is Rain just look at the weather station where cold fronts and warm fronts meet this is what was happening in my room and probably many other grow room with direct outside air in colder climate areas

 

[pcduck]

Just like a glass of ice tea on a hot day, there is condensation.

Condensation will occur where the air molecules are slowed down enough to come together and form moisture.

The colder the outside air and the warmer the inside air the more condensation will occur. I call this the condensation line, this can easily be seen on a propane tank that is being used on a hot day.

HushPuppy's big advantage is mild outside temps and whatever condensation occurs is most likely draining down his duct work as he is pulling from the floor. If he was pulling fresh air from his roof, gravity more then likely would drain this into the lights. just my$0.02

 

[Hushpuppy]

Hey guys I don't have any pics to show my setup but I will take some tomorrow and post so that you can see it.

My holes are in the floor of my building and connect to outside air that is under the building. The air that comes into the building through the holes is the same temp as outside(in the winter) and about 10degrees cooler than outside air in the summer. I don't have any of the sweating issues that yall have seen.

I understand the sweating and "dew Point" of warm vs cool air and the warm/cold fronts. My winter temps and humidity vary greatly here in NC, some days it 60 and the next its 35. It can easily go from 26 over night to 65 in the daytime. I think the key to mine is that there isn't a hard warm/cold line anywhere within my building. The key to the sweating glass is that the glass is cold and the moist air is warm, so that when the warm moist air contacts the cold object its temp is dropped below its dew point, which in turn causes the moisture to precipitate out of the air mass.

For my situation it is the opposite. I am injecting colder, (relatively)drier air in into warmer, dryish air(30-50%). It may be that my internal air is even dryer than that but for the outside air bringing in enough moisture to raise my humidity to present levels.

DF("doesn't matter if out side RH is low once cold and hot meet there is Rain just look at the weather station where cold fronts and warm fronts meet this is what was happening in my room and probably many other grow room with direct outside air in colder climate areas") You are looking at it backwards. If the cold airmass is at 100%humidity, regardless of its temperature(relative typical environmental temperatures), if it is injected into a warm airmass at any temp(within typical environment temp range) with a RH of less than 50%, it will not cause precipitation. The reason is that the heat energy in the warm air will mix with the cold air and the total air mass will settle to a temperature that is lower than the original warm air temp but higher than the original cold air temp. While the warm air will contract some, at 50%RH it has enough room to contract without reaching saturation. At the same time the cold air will expand from the heat energy, which will cause its water holding capacity to increase which will lower its relative humidity (which already has less water in it because it being cold can't hold as much water as warmer air).

Now if you were injecting warm moist(75%RH) air into cold air that is at 50%RH then you would have a condensation issue as the lowering of the net air temp would mean less water holding capacity for the already high RH warm air. You have to look at it in terms of capacity and saturation of the air masses and the amount of difference between the two air masses.

 

[Sparkie]

I'm using my iPad & my picture sizes are to big to upload :-(

My 6" exhaust fan pulls 552 m3/h and my intake is 325 m3/h my current outside temp is -4 degrees c my room temp is 10 degrees c and my room outside the tent but inside the ply boarding is 20 degrees c my grow area varies from 27 degrees c to 30 degrees c depending on if and when my fans are running thru my temp controller, I run a hydro setup 4 pot, I have a small fish tank pump circulating the nutrients in the res with an air stone and fish tank 100w heater to keep the nutrients warm, my r/h is currently 35, how's this sound senior growers?

 

[Hushpuppy]

That all sounds solid. The grow temps can be a bit lower. I wouldn't allow it to go higher than 28c in the grow area and ideal temp would be around 24c. And you want to maintain about 18c in the hydro tank but don't let it get any lower than 15c, no higher than 20c.

 

[Sparkie]

Cheers for the info hush, my ph is currently 4.2 will this have any bad effects on the plants? I would top up the res to bring the ph up to around 5.4 ish but it's pretty full at the minute

 

[The Hemp Goddess]

Cheers for the info hush, my ph is currently 4.2 will this have any bad effects on the plants? I would top up the res to bring the ph up to around 5.4 ish but it's pretty full at the minute

Yes. If your pH is at 4.2, you might as well be running straight water. At that pH level, the nutrients are not available to the plants. It is critical with hydro that you keep your pH levels between about 5.3 to 6.0, with 5.8 being what most strive for. I do like a little drift, but 4.2 is way way too low. You need to correct that now. What do you use for pH up and down

 

[Locked]

I am with THG, you need to adjust your ph up as soon as possible. 4.2 is ridiculously low. I don't do a lot of hydro but I do know you need ph up and down, a good ph meter and a ppm meter.