a question on cooling and venting

So let me first say I am not new here,I just had to get new acct due to computer problems.I have completed plenty of grows and have a good amount of knowlage and all the ins and outs of my set up specificly. I had to totaly redue what I had so figured go bigger and better built this time around.

So lets get into the setup and qustions....

Room- 10x10x7 inside a larger room. Shitty part is its a second floor so it gets hot during day
The original room was 8x8x7 mylar,tuff-r 1/2inch thick insulation and plywooded.
The new room so far is mylar,mostly tuff-r 1/2inch but some of the cheaper 1/2in insulation and no plywood

Co2- inuse so the room is a sealed unit.


Lighting- original was 1 1000w and 3 600w all hps high spec high lumens bulbs.
New room is starting w 2 1000w and 2 600w hps but i wanted to add a 600w mh blue spec to center if possible
All lighting is digital w ballests out of room and air cooled hoods w a 8in intake and 2 8inch exhaust. All four are vented but the one i want to add wont be.

A/C- Hair 8000btu w energy saver mode.rated for 350-550sqft. With old room and the 2 1000w /2 600w set up it would keep it cool enough that it could shut off for a bit and never went over 80 if i set it right. I did kinda feel like it was working a bit more then should. The back of the a/c pushes the hot air into the hotter room which is already hot from sun then i have to try to fan that hot air out.I pulled a screw from back of case to let water drain and it would fill a 5gal pail in 2days or less .
Now w 2/1000w and 2/600w on it spikes to 87 unless i shut off 1 1000w.There is also no water coming from back now.

I dont know if it cuz its bigger and no plywood or if the a/c is shitting out or what.And i surly cant add my other 600w if its this hot and it wouldnt b vented either. I have a chance to get a new ge 18000btu a/c for $300 which is a deal but its huge and heavy and im pushing limits on power to grid already id say lol.
if your an experienced producer ple
ase feel free to enter advice or oppinions...if your a begginer or just here to bash others thoughts please dont post to this thread as i need real help like days ago.thank you all in advance

You already know the answer as you state the exhaust air from your AC is hot. Duh. The principle of refrigerated air. You have to duct the exhaust air outside. Being sure to go bigger rather than smaller you need to duct this air outside your home. Using 6" dryer line with TWO inline fans if this run is over 10', reduce the exhaust duct by taping or shielding but feeding into your new exhaust duct. Keep the exhaust as straight as possible with no dips, bends or rises IF POSSIBLE! Doing this it is impossible to duct too large but very easy to go too small and block the exhaust and burn it up.

i know what you mean.there is an open window and the hot air exscapes some but its still hot. the system worked fine before as long as i emptyed the bucket thats why i was thinking its in the insulation or the ac has been run with the hot air around it too long.

So lets say because the ac still puts out cold air and it did work before i upped the wattage the ac is good. Ive always woundered if it be worth the cost and if it be a fire hazard too due as you said and box back of ac and duct directly to the vent?? anyone done this w a simalar set up and improved there temps?? i figured i would due this next but didnt want to if didnt have to cuz it worked good before just a lil hot in the work zone lol.

so any one out there that has a 10x10x7 or close to it and running around 3500-4000w with an a/c installed?? Id like to hear some btu sizes and temperatures to compare and see if I need to go buy the 18000btu a/c or if people have used and made a 8000btu work for this size room with same wattages. Thanx