Dr.Nick Riviera
Well-Known Member
or huff off the freon.lol
Negative Pressure Causing Damage
- Thread starter jsisko01
- Start date
since1991
Well-Known Member
I hear ya there. Ive had spots in the eastside ghetto of Flint Mich before. Got the hell outta there quick as i could. Rough. They would look at the outside condenser of an ac unit as a prize inna cracker jack box. Baseheads and heroin junkies are a problem in my town. And they will clean yer house out...give them half a chance.
Dr. Who
Well-Known Member
Okay I'm really hoping someone can help me out here.. There's a few ways I was thinking of dealing with this, but I want the easiest and cheapest ideas first. I have a 12x20 ft sealed grow room (1680 cubic ft) and am using a Whynter 14,000BTU dual hose ac unit (ARC-14SH). This thing is exhausting way more air than it is intaking. To the point where my vinyl flooring is parachuting and stretching / ruining it. I was under the assumption no dual hose air conditioners create negative pressure until I started doing some googling. If I do not take care of this quickly I'm afraid it's going to cause damage to the wood as well. The floor is plywood underneath the vinyl and I even feel the nails starting to raise.. It's bad. I also have a small hole in the ceiling where my light fixture is and it's sucking large amounts of hot air through the attic as well. I know I need to seal this soon but the main concern is eliminating the pressure. There is an extra air intake panel on the back of this unit which comes with a carbon filter. I am unable to tell if this intake is just being blown back out of the fan or if this is creating the extra exhaust air. Check out the unit on Amazon - https://www.amazon.com/Whynter-Portable-Conditioner-Heater-ARC-14SH/dp/B002W87P9C
I am against the whole "passive" air intake method. If I do not correct the ac exhaust, I will just be dumping large amounts of CO2 out of the room. I wanted to keep my "seal" as best as possible. Do you think running an extra fan through the intake hose would help? The only issue with that would be that it will remain blowing even when the ac unit shuts down and therefore possibly causing a positive pressure scenario, or even creating positive pressure inside the ac unit (if it's truly sealed). My last option I'm thinking would be to tape up and seal that back intake panel (the one on the back of the unit that takes air from inside) and create a new vent so it intakes from the outside as well. Or cut a hole in the original intake to merge them both to suck air from the same hose?
What do you all think? I really need some help and ideas. On another note.. what are you guys filtering the intake with without reducing suction? So far I only put in bug screens. Thanks
YOU DON'T have a neg pressure problem!
The AC unit has the RH so low at the floor level the tiles have "dried out" and are curling from cold dry air that has made the cheap glue that holds them to the floor to fail !!!!
Sometimes the stuff use guys come up with !!!
Roger A. Shrubber
Well-Known Member
i actually followed the link and read their description.
Dual Hose Exhaust for Optimal Airflow and Efficiency
To cool your space efficiently, the ARC-14S draws warm air from both the inside and outside environment and converts it into cool, clean air. Warm, humid air is then expelled from the room through the exhaust hose. Similar to traditional window air conditioners, this dual system creates improved airflow and efficient cooling.
the unit draws in air from the room through the carbon filter. one of the hoses is supposed to be sucking air in from outside, and the other hose is the exhaust, if you don't have both of those hoses outside, you're doin it wrong.
Dual Hose Exhaust for Optimal Airflow and Efficiency
To cool your space efficiently, the ARC-14S draws warm air from both the inside and outside environment and converts it into cool, clean air. Warm, humid air is then expelled from the room through the exhaust hose. Similar to traditional window air conditioners, this dual system creates improved airflow and efficient cooling.
the unit draws in air from the room through the carbon filter. one of the hoses is supposed to be sucking air in from outside, and the other hose is the exhaust, if you don't have both of those hoses outside, you're doin it wrong.
since1991
Well-Known Member
Your not running a sealed room my good.man. I can bet that most of your co2 is being blown out. Do you have a simple co2 ppm monitor?Thanks for the reply. I have a Whynter ARC-14SH dual-hose portable AC running right now. It is 14,000 BTUs. It was rated for a 500 square ft room. If I can get this to work, that would be great. It cost me like $570. I feel like this should be sufficient for my room.. And it's too late to get a refund for it now
I have 6 600W LEDs from HydroponicsHut, and a Gotham Hydroponics 8-burner for CO2. This is a completely sealed grow room. No outside air is flowing in. Maybe my AC unit has an air leak and that's why it's blowing out more than it's sucking in? When I go outside.. the intake feels very weak. The exhaust is very powerful.
I appreciate your reply but you are completely wrong lol. Do you think I'm not monitoring my RH, temperatures, etc? I know there are a lot of newbies on here but I'm not that unintelligentYOU DON'T have a neg pressure problem!
The AC unit has the RH so low at the floor level the tiles have "dried out" and are curling from cold dry air that has made the cheap glue that holds them to the floor to fail !!!!
Sometimes the stuff use guys come up with !!!
I also stated that I have a vinyl flooring, it is the cheap roll out stuff. Not tiles. And I did not glue it down, I laid it over my plywood floor and only pinned it down with the baseboards (didn't think glue was necessary in my situation). 2 minutes after turning the AC unit on, you can watch the floor slowly raise and poof up like a balloon lol. It will raise a couple inches and feels like you're walking on a trampoline.Anyways, thank you all for your help but this problem seems to be solved now. Someone referred me to a great post on how the Whynter dual hose units are not truly air tight. There are multiple air leaks within the unit, that are creating it to suck air from inside and blow outside. I will open the unit, and seal these chambers myself and reroute the drain pipe.
Here is the link to my other post so you can all see my setup/equipment used:
https://www.rollitup.org/t/portable-ac-bad-negative-pressure.914017/
Here is a link to the tutorial on how to make a truly sealed dual-hose unit:
https://www.rollitup.org/t/modifying-portable-a-c-for-use-in-sealed-grow-room-w-co2-tutorial-w-pix.887831/
Dr. Who
Well-Known Member
"New member" tends to make us answer so sometimes. Sorry......LOLI appreciate your reply but you are completely wrong lol. Do you think I'm not monitoring my RH, temperatures, etc? I know there are a lot of newbies on here but I'm not that unintelligent
Anyways, thank you all for your help but this problem seems to be solved now. Someone referred me to a great post on how the Whynter dual hose units are not truly air tight. There are multiple air leaks within the unit, that are creating it to suck air from inside and blow outside. I will open the unit, and seal these chambers myself and reroute the drain pipe.
Here is the link to my other post so you can all see my setup/equipment used:
https://www.rollitup.org/t/portable-ac-bad-negative-pressure.914017/
Here is a link to the tutorial on how to make a truly sealed dual-hose unit:
https://www.rollitup.org/t/modifying-portable-a-c-for-use-in-sealed-grow-room-w-co2-tutorial-w-pix.887831/
I put in central heat/AC to a free standing structure (larger) .....No chance of air pressure problems...BUT,,,WOWSER on your reply,, has me understanding now! That's FAR worse then it should be.....
A mini split is STILL a viable option by mounting it on the roof to thwart those with theft in mind.. Possible?
Budley Doright
Well-Known Member
I just had to apologize for saying the dual hose doesn't create negative pressure ...... They do and they are crap. if there is a panel on the back to convert it to a one pipe try duct taping that seam it may help a bit.
bryan oconner
Well-Known Member
glad you have it fixed up .
Budley Doright
Well-Known Member
You can mount them pretty much anywhere you can get power to them and get lineset to the head (indoor unit), most allow long lineset lengths of 90 feet more or less. You may want to consider one that allowed for cooling in lower temps and is also a heat pump if needing heat. High up on wall brackets work well also.
since1991
Well-Known Member
My split allows for cooling even if its cold as shit outside....but i dont use it. I have a fancy filtered intake that i open up just for the winter months...works just like a.c. I figured it pretty ass backwards to use the split in February in Michigan when its 18 degrees outside. Iam also thinking about short 1 min burst everyfew hours an exhaust when lights are off. A fancy louvered type dealy. Something about ethylene buildup i read but honestly its not needed in my spot. But ive thought about it.
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since1991
Well-Known Member
Alot of times sealed rooms...especiall6 the bigger ones need a dehuey in conjunction with the split. I broke down and forked over the duckets for a santa fe classic. Those H Depot mom and pop dehueys just dont cut it. But those cheapie window shaker ac's and dehueys i do use in my drying curing room. They work great together getting a perfect dry and cure everytime.
bryan oconner
Well-Known Member
i use window units they work fine for me . but I am able to have a outlet or cut a hole into the wall . or make home made ducks . my window unites cool just as good as a mini split from experience . only reason to buy a mini split is because its impossible to use a window unit . I bought a 24000 btu window 325 and a 18500 window unit 300 menards gree brand . bought in the winter on sale . quiet cool . mini splits would of cost me 2500 .
since1991
Well-Known Member
Mini splits are damn near twice as cheap (efficient) than window shakers with equal BTU's on a yearly basis depending on SEER rating. Also...and any shaker ive ever used leaked some growroom air. Some units much more than others. There are MANY reasons to choose a split over a shaker.
Budley Doright
Well-Known Member
Ya most ductless do, used a lot in server rooms.
DemonTrich
Well-Known Member
I'm going to try using winter air vs my ac when the weather turns. Just have to figure out how to set my temps accordingly.
Budley Doright
Well-Known Member
I have an exhaust fan and electric heater hooked to a stat that keeps room at 75 lights on and 65 lights off in winter and I shut the thing down in the summer, just can't deal with the heat and the sun is free .
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