Portable AC Unit for 1x1m

Greetings, I wanted to install a split ac in my growroom but I`ll be moving soon so the install costs (about 130$) won`t compensante, so I thought I would buy a Portable AC, and install it diretcly inside my growroom (It`s made of pandafilm, so my ideia is to cut the space for the ac unit, install and take the tube to the window where the air from the growtent goes out.
So my questions are:
1 - Will it work?Considering the whole unit (At least 8000btu) will be focused only on this 1m2?
2 - How much of a humidity drop can I expect from the ac?My city usually is 30% RH, but in my previous crop, right at the end it reached 85%, so my plants started getting mold, really pissed me off because I had to cut it at once and make hash out of the good parts, so I would like to make the AC unit work in a way that makes the humidity be as I wan`t it to (Using timers or an arduino, don`t know, ideas are always welcome)
3 - How should I set the timers of my exhaust?Obviously it can`t run full time anymore, otherwise I`ll be just thworing energy and money away, so should I turn the exhaust on and off for how many time, in the night per example, is it a good idea to leave it totally off?Since plants don`t need CO2 at night
Extras:Isolating the room and adding co2 is not an option right now, but it surely will be, once I move from this house, I`ll make only 1-2 crops on the system mentioned above, so anything that works is fine, but the AC is very needed because it oftens passes 30 celsius on the growroom, waay too much, got an hermie for that once.

Your light will determine the amount of heat that needs to be removed. In that size space I can't see you using anymore light than a 8k BTU/hr air conditioner could handle.

You can estimate the heat load by taking the light wattage and multiplying it by 3.5. That will get you close. If you use a double ended light multiply by 4. If the ballast is in the room add 10%.

Renfro said:

Your light will determine the amount of heat that needs to be removed. In that size space I can't see you using anymore light than a 8k BTU/hr air conditioner could handle.

You can estimate the heat load by taking the light wattage and multiplying it by 3.5. That will get you close. If you use a double ended light multiply by 4. If the ballast is in the room add 10%.

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Forgot to mention, I use 200w of Citizens and 100W of Cheap Chinese Leds

My biggest issue is with how much air removal is the minimal I can remove, I wan`t to timer my exhaust so it exhaus`ts the minimum possible to keep a nice co2 ammount in the tent, but not using the AC that much, to diminush costs, the exhaust itself is 250CFM at maximum

If you setup the AC correctly it could bring fresh air into the area.

guerreiroweed said:

Forgot to mention, I use 200w of Citizens and 100W of Cheap Chinese Leds

My biggest issue is with how much air removal is the minimal I can remove, I wan`t to timer my exhaust so it exhaus`ts the minimum possible to keep a nice co2 ammount in the tent, but not using the AC that much, to diminush costs, the exhaust itself is 250CFM at maximum

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Easier to use a thermostat wall plug for the exhaust when its hot. Not sure how you would achieve temp control with a timer

Boatguy said:

Easier to use a thermostat wall plug for the exhaust when its hot. Not sure how you would achieve temp control with a timer

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I think with the AC he was only going to use the exhaust for fresh air (co2).

If the AC is one that comes back on after a power outage, you put it on the timer with the lights (provided the voltages are the same and you have enough available amperage on that feed). This would kill the AC when lights are out. Then have the exhaust fan on a timer so it can run, perhaps even periodically, when lights are out to prevent stale air and humidity spikes. The AC would act as your passive intake when the lights are off and the blower runs. The trick is to find the right temperature setting on the AC as it will be reading the air temp it is pulling from the area outside the grow.

Many portable AC units will pull air from the sides or back, cool it and blow it out the front. So with the AC outside the tent you can count on the AC unit to bring in fresh air (CO2) when the lights are on.

This setup would save energy and make happy plants.

Renfro said:

If the AC is one that comes back on after a power outage, you put it on the timer with the lights (provided the voltages are the same and you have enough available amperage on that feed). This would kill the AC when lights are out. Then have the exhaust fan on a timer so it can run, perhaps even periodically, when lights are out to prevent stale air and humidity spikes. The AC would act as your passive intake when the lights are off and the blower runs. The trick is to find the right temperature setting on the AC as it will be reading the air temp it is pulling from the area outside the grow.

Many portable AC units will pull air from the sides or back, cool it and blow it out the front. So with the AC outside the tent you can count on the AC unit to bring in fresh air (CO2) when the lights are on.

This setup would save energy and make happy plants.

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Perfect, thats exactly what I want to do, the problem will be only to find the right timing to turn the exhaust on and off @ night without a CO2 meter, so I decided to post, maybe someone tried the same, 1m² tents with 300w led setups are very common after all.
Another question would be, since the AC Unit is pulling more air inside the box (in the day), it`ll be expelled at some rate from the hole my exhaust leaves in the tent, because of the increased pressure caused by the air on the tent, right?
Also the passive air intake from the AC Unit (While turned off) is enough for me to permanently close the holes I use for passive intake?

An ac for 300 watts of light? I dont see a need for ac at all imo bring in fresh air with fans moving air in room...I run a 700 watt cob light with no ac.

Gorillaglue4u said:

An ac for 300 watts of light? I dont see a need for ac at all imo bring in fresh air with fans moving air in room...I run a 700 watt cob light with no ac.

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I live in a subtropical country, as I mentioned above, regular temperature is 30 Celsius inside the grow, usually outside is about 29, my leds don't produce much heat, my exhaust can handle it easily, the problems lies in the temperature of the air itself, it already comes in hot...