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[-C@jun-]

Ran the one exhaust fan today with the other off as a passive intake. Temps were 87F. Trying to get everything dialed in. Would the two fans running exhaust change the temps? Lift up the panda film by the door about 3" to act as a intake instead of cutting holes to test?

 

[LEFTHAND]

Ran the one exhaust fan today with the other off as a passive intake. Temps were 87F. Trying to get everything dialed in. Would the two fans running exhaust change the temps? Lift up the panda film by the door about 3" to act as a intake instead of cutting holes to test?

wow 87F do you have another fan??? if so use it to bring in colder air... that will help you dial in your temps much easier then passive intake...
theres my opinion hope it helps...
LH

 

[zem]

did you make an opening for air intake? that opening had the fan on it would be an obstacle for air to come in. however im quite sure 2 fans exhausting together with proper intake holes would suck out more cfm, laws of physics

 

[-C@jun-]

wow 87F do you have another fan??? if so use it to bring in colder air... that will help you dial in your temps much easier then passive intake...
theres my opinion hope it helps...
LH

Yes I unplugged the lower fan to test as a passive intake and thats when i got the high temp of 87. When I run the other fan as a intake I run high 70's but both fans are 250cfm. I'm pulling as much as i'm bringing in slightly because the exhaust is pulling through the hood but my temp stays at 78F. Is it one of those if it works don't mess with it?

did you make an opening for air intake? that opening had the fan on it would be an obstacle for air to come in. however im quite sure 2 fans exhausting together with proper intake holes would suck out more cfm, laws of physics

Yes I left the fan in. I don't want to cut more holes in my temp wall and have to cover them or replace the board if it doesn't work. My question is with both fans running as exhaust and 2 holes 6" working as passive would that control the temps? It would move more air thats a fact but would it control the high temps.

 

[zem]

try working one exhaust fan but with a slightly open door to allow passive intake and see wat happens, to answer your Q yes it should replace the hot air quicker hence better lowering of temps

 

[-C@jun-]

82F with a 3" crack at bottom of door. Still with intake fan I got 78F after 3 hours running. Is it one of those if it works don't mess with it even though i'm pulling as much as i'm introducing? Or would it be better to run both 6" as exhaust and put 4 6" holes and work them as passive intakes i believe I could get the under 80F with both fans exhausting and 4 holes running passive if I would need that many holes with 2 fans running. If I would go that route if better for my plants then just keeping the one fan as intake and other as exhaust I would run both fans as exhaust and start off with 2 holes test and see temps and move up. Or is to many holes a bad thing?

 

[zem]

it's your call cajun it helps just a bit using intake especially if you have curves in the ducts but its effect would be much bigger if 2 were exhausting, how high are the temps outsid? try running both fans now it is probable that climate changed since the last time you tried it with 2 fans. i'd bet that your temps would go to like 80-81 with both them on now

 

[-C@jun-]

It is cooler because it is night. It's like 73-75F outside the area. 65F outside house. I tried it during the day with the intake fan on. Outside during day is 77F. Room temps were 73F. I monitor the temps in the room quite often either open door to bedroom or close it and also have a/c heating from home to keep temps 70-75. I either open the a/c vent to introduce a/c during hot day. During the cold short spell we had I kept a/c vent closed temps dropped at night to 65F in room door closed. Humidity stays 37 veg. Now with that crack at bottom of door my humidity was 36 in flower area. Also I had problem with over flow today and have been in there recently filling and testing so that maybe why humidity is high in there. I was running a 3/4 over flow have to go and get a 1 1/2 bulkhead fitting the 3/4 isn't draining quick enough. I have a 500GPH pump it puts out like a garden hose.

Appreciate the help Zem.

I will be buying another 250 after hearing your posts. I would like to keep the intake. Should I put a passive intake hole or should the one intake fan be good enough for the 2 exhaust all same cfm. Basically what do i want more exhaust then intake or equal? I have one exhaust for my hood. Hood is open to room on opposite side.

 

[LEFTHAND]

It is cooler because it is night. It's like 73-75F outside the area. 65F outside house. I tried it during the day with the intake fan on. Outside during day is 77F. Room temps were 73F. I monitor the temps in the room quite often either open door to bedroom or close it and also have a/c heating from home to keep temps 70-75. I either open the a/c vent to introduce a/c during hot day. During the cold short spell we had I kept a/c vent closed temps dropped at night to 65F in room door closed. Humidity stays 37 veg. Now with that crack at bottom of door my humidity was 36 in flower area. Also I had problem with over flow today and have been in there recently filling and testing so that maybe why humidity is high in there. I was running a 3/4 over flow have to go and get a 1 1/2 bulkhead fitting the 3/4 isn't draining quick enough. I have a 500GPH pump it puts out like a garden hose.

Appreciate the help Zem.

I will be buying another 250 after hearing your posts. I would like to keep the intake. Should I put a passive intake hole or should the one intake fan be good enough for the 2 exhaust all same cfm. Basically what do i want more exhaust then intake or equal? I have one exhaust for my hood. Hood is open to room on opposite side.

you need equal cfm to run intake and out.well you should. if your exhaust is greatter then your intake you should get a fan speed controller.. to dial it in..
but the air you bring in you want colder then the rest of the room..
if not then you shoulr have a couple passive air intakes... to make up for it.
as for your drain issue you could have put a T in you fill line.. turned it a 1/4 turn once again dial it in.
LH

 

[-C@jun-]

you need equal cfm to run intake and out.well you should. if your exhaust is greatter then your intake you should get a fan speed controller.. to dial it in..
but the air you bring in you want colder then the rest of the room..
if not then you shoulr have a couple passive air intakes... to make up for it.
as for your drain issue you could have put a T in you fill line.. turned it a 1/4 turn once again dial it in.
LH

Appreciate the knowledge LH
Yeah I do have a T with a ball valve on the fill side. I put a 1 1/2 over flow in this morning. Still wants to go over it. I'm gonna make it a inch shorter hoping the pressure will push it out the drain faster if not i'm going to open that ball valve some. As for the fans there both the same cfm. Except exhaust is pulling through hood not stand alone. I have another 250cfm on the way to run as just a exhaust for the room and I'm going to make another hole or 2 for passive. I ran it this morning as well for 2 hours intake fan on with room sealed. Temps read 83F. I have a window unit in the shed I may put in the bedroom to help keep room cool over hot summer. I can run ducting from it to chamber then I could intake cool ait opposed to the room 75F temps

 

[LEFTHAND]

Appreciate the knowledge LH
Yeah I do have a T with a ball valve on the fill side. I put a 1 1/2 over flow in this morning. Still wants to go over it. I'm gonna make it a inch shorter hoping the pressure will push it out the drain faster if not i'm going to open that ball valve some. As for the fans there both the same cfm. Except exhaust is pulling through hood not stand alone. I have another 250cfm on the way to run as just a exhaust for the room and I'm going to make another hole or 2 for passive. I ran it this morning as well for 2 hours intake fan on with room sealed. Temps read 83F. I have a window unit in the shed I may put in the bedroom to help keep room cool over hot summer. I can run ducting from it to chamber then I could intake cool ait opposed to the room 75F temps

is your over flow on the side or in the middle?? and what are you using for a screen just a plain old bulk head fitting screen?? i had to cut a few of the lil bars in my set up to keep it at a nice drain stream.. just cut one here one there opened up the screen a lil im also runnin 1" lines just a thought..
LH

 

[-C@jun-]

No I have it cut at a 45 with like a wire screen. I can't really poke holes because of the hydroton. The fill and over flow are in middle of tub. 1/2 fill off to left and right about 1" from fill a 1 1/2 over flow going up 10" to peak. I'm about to go cut it to 8" right now and will post how it turns out.

 

[LEFTHAND]

No I have it cut at a 45 with like a wire screen. I can't really poke holes because of the hydroton. The fill and over flow are in middle of tub. 1/2 fill off to left and right about 1" from fill a 1 1/2 over flow going up 10" to peak. I'm about to go cut it to 8" right now and will post how it turns out.

its probally your screen getting glogged.. mudding up from the hydroton...
that would be my guess.. the filters i as mentioning have like a 1/8-1/4" gap between em.. they for surely will stop hydroton and big particls but not the fine shet... thats what the filter on the pump does as you already know hehehe.... i would look into getting rid of the screen.. it will only cause problems to you..
LH

 

[LEFTHAND]

Heres one of my over flow screens for a refrence..
LH

 

[-C@jun-]

I know exactly what your talking about. I had got them for my veg tray but took them out. I cut the pipe down 1 1/2 and have been running it now for 35 minutes and is staying at a level opposed to rising. All I have left is to get the temps out of the 80's. Have another 250cfm coming i'm going to ad another exhaust and 1 or 2 passive intakes or 1 going to a window unit.

 

[LEFTHAND]

good to hear you got er.... i figured you knew what i was talkin bout but ya never know ... i would drop the water leval just a tad bit more if it was me.. just till you cant see the water no more.. in the one pic there i can see the water perfectly...
hope that screen dont plug up on yas..
LH

 

[-C@jun-]

Appreciate it LH.
Yeah I was hoping it would be enough but since you mentioned it guess i will bail out the hydroton in the morning a cut her down another inch.

 

[zem]

temps inside the room should be slightly higher than outside temps if your venting is good, the difference should be 2-4 degrees, if its more then your venting insufficiently. it is very probable that your airflow is being disrupted by obstacles and if your room is tight the oscilating fan could further disrupt it rendering that exhaust fan almost useless. i had an oscilating fan that raised my temps like crazy it turned out that the strong wind inside this tight area was preventing my exhaust to suck air out. the intake and exhaust holes should have NO obstacles infront of them, if you place a little gravel in your exhaust duct the wind molecules would be bouncing off it and then going sideways bouncing into flowing air molecules sort of like a crash on a busy highway. i'm just trying to explain the basics of airflow so you could know wat to do. addingmore cfm is not always the answer, make full use of your current fans efficiently then see what you need, cheers

 

[LEFTHAND]

temps inside the room should be slightly higher than outside temps if your venting is good, the difference should be 2-4 degrees, if its more then your venting insufficiently. it is very probable that your airflow is being disrupted by obstacles and if your room is tight the oscilating fan could further disrupt it rendering that exhaust fan almost useless. i had an oscilating fan that raised my temps like crazy it turned out that the strong wind inside this tight area was preventing my exhaust to suck air out. the intake and exhaust holes should have NO obstacles infront of them, if you place a little gravel in your exhaust duct the wind molecules would be bouncing off it and then going sideways bouncing into flowing air molecules sort of like a crash on a busy highway. i'm just trying to explain the basics of airflow so you could know wat to do. addingmore cfm is not always the answer, make full use of your current fans efficiently then see what you need, cheers

i have also ad that problem.... try having the fan blow towards your exhaust... or towards and at the floor or up high... keep a circle going with the air flow.... it dosent seem like much but them big fans do push and pull alot of air...
LH

 

[-C@jun-]

I have the fan on pivot left to right. Intake sucking from bottom blowing in back right corner. The exhaust has a obstacle it is sucking through hood from left side of area. Thats why I want another exhaust. If that doesn't work I'm putting a window unit in the bedroom window and routing fresh cool air straight into room through a passive hole. What do you fellas think about that? The light is hot and should keep humidity down. It's at 21-25RH with room sealed. Shouldn't bring it over 40RH. My veg area stays at about 38RH would the unit effect that?
For the fan won't that keep my stems strong where they won't bend and fall over from the weight of the buds?
My temps are about 5-6 degrees difference from outside temps. Should I disconnect fan from hood? I'm going run everything with oscilating fan off. I let you know how that goes in about 2 hours.