Using AC on sealed room in winter

guy incognito

Well-Known Member
I have a sealed room running co2 in my basement. I have air cooled lights, but the temp the room is still getting high. When the temp gets high enough the AC kicks on. I hate running the AC unit to cool the room when it is 7* outside. I'm also afraid it's going to damage the AC unit, and I would be fucked because there is no place to buy an AC unit when its 7* outside. The AC seems to run the same amount no matter what temperature it is outside. The basement is well insulated from the outside in the summer, so it stays nice and cool, so the AC just needs to run to cool the excess heat from the lights. In the winter it seems to be the same scenario.

Anyone got any suggestions? Should I just hook up an exhaust fan/filter and run that? Would it be ok to pull fresh air from outside, even if it is close to 0*F?
 

BelieveInJesus

New Member
You can pull in air from outside, but you have to really be diligent about it and not let too much in and freeze your plants. I'm a little confused as to why you are worried about your air conditioner. Is it because the air coming in form outside is so cold?
 

Metasynth

Well-Known Member
You can pull in air from outside, but you have to really be diligent about it and not let too much in and freeze your plants. I'm a little confused as to why you are worried about your air conditioner. Is it because the air coming in form outside is so cold?
I think it's because it's really cold outside, and he's worried about damaging the unit...plus, who runs their ac when it's 7 degrees out?
 

guy incognito

Well-Known Member
I think it's because it's really cold outside, and he's worried about damaging the unit...plus, who runs their ac when it's 7 degrees out?
Exactly. Huge waste of energy. Suspicious. Also they are not designed to be operated in 7* weather. The manufacturers usually say not to use them below about 60*, but you can safely go much lower. It would be nice to drop my electric bill under $400 too.
 

jrainman

Active Member
I would not worry to much about harming the a/c the heat load (BTU) is there for your unit to say go on, some better a/c unit have what is called a LPC (Low pressure control that wont let a a/c kick on below a certain outside ambient ait temp, In reality the refrigerant (freon) is being cooled at a faster rate because of the outside ambient temp is colder and keep the compressor much cooler than in the summer.. so as to wear and tear on the unit ,not much . I can help you solve your problem but to need some info on your room , Do you have exhaust ....... size of room ..........Lights How many total and wattage. what is the temp in your room.
 

guy incognito

Well-Known Member
Room is approximately 20'x8'. I have 3 4x4 tents with 2400 watts total. I have a sentinal chhc-4 controller. Lights are air cooled - Currently the intake and exhaust come to/go to the other part of the basement that is not part of the room. CO2 is kept around 1000 during lights on. I have an intake/exhaust that leads directly outside - it was previously used to cool the lights, but I was getting condensation on the ducting from the cold weather outside so I switched it to my current set up which uses air from the other side of the basement to cool the lights. The 2 vents to the outside are capped right now and not being used.

My concern is that the AC was designed to use when it is hot outside, so the outside condenser is engineering to condense the refrigerant while the ambient temp is 60-110*F. Operating it while it is 7* outside might cool it too much, which when the pressure is released will make the cool side much too cold, cold enough to cause freezing on the coils and eventually lead to water getting into the compressor and damaging it. I know some unit have a lpc that wont let the ac kick on below a certain ambient temp, but I also know some just alter the way the unit runs. For example if the ambient temp drops low it will simply not run the fan on the condenser, therefore not cooling it as much so you avoid damaging the unit. I have a thourough understanding of thermodynamics and how the units work, but I don't have much real world experience dealing with units, so I don't know if my unit is equipped with one of these or not. It seems to be operating just fine, but I would like to avoid future damage. I would also like a more economical option. It seems ridiculous to be running my AC in the basement, and the furnace for the rest of my house.
 

BeaverHuntr

Well-Known Member
Thats crazy I'm in AZ and I run a sealed room with two 1000W air cooled lights and even though it only gets like 40 degrees at night my temps never run higher than 75 in the winter and I never have to use the AC.. In the Summer when its 110 degrees and my AC is on and my lights are running the temp never gets above 88 degrees... I think you need a stronger fan to pull that hot air outside the room.
 

jrainman

Active Member
Basement grow ,outside ambient he says 7 deg f tells me he has a boiler heating his house at 7 deg f the boiler is most likly old and running a real lot to compensate for the extremly cold temps he is having rite now ( heating system) close to his grow area and or heating pipes that are not properly insulated and maybe even passing through his grow room creating even more heat in the grow room.Just a guess
 

dbkick

Well-Known Member
I pull air from the garage in the winter. you'll more than likely get some condensation like that though. I used insulated flex and had no more condensation which is strange since the cold does meet the warm at some point.
 

dbkick

Well-Known Member
If you would like to cool your room and NOT have to use AC then try one of these View attachment 2493180 WHen used in conjuction with a chiller can cool your room very quickly.
I own one of these and it's sit idle for awhile. I do however intend to put a res out in the garage and use this to cool the co2 generator. I'll secure the ice box and fan to the top of the tote and use the cold air to chill the water, should save a few amps by not running a chiller.
 

guy incognito

Well-Known Member
Basement grow ,outside ambient he says 7 deg f tells me he has a boiler heating his house at 7 deg f the boiler is most likly old and running a real lot to compensate for the extremly cold temps he is having rite now ( heating system) close to his grow area and or heating pipes that are not properly insulated and maybe even passing through his grow room creating even more heat in the grow room.Just a guess
No boiler, its forced air heater. Ambient temp on the other side of the basement is about 66*F.

Even when I was pulling air from outside and over my lights and exhausting back outside my room was getting too hot. Once winter and sub-freezing temps set in I was getting massive amounts of condensation on the inlet, all the way up to the 2nd light, so I was getting drips on my plants. The air exhausting felt pretty warm to me. The AC still had to run to keep the temperature at 82*F. These lights just dump massive amounts of heat and the basement seems to be trapping it very efficiently, or rather seems to not be dispersing it as fast as it's getting generated.

I thought switching from outside air to basement air to cool the lights would heat up the other side of the basement, but it's not. The exhaust feels warm like my furnace vents, but it doesn't seem to be heating up the other side of the basement very much at all. The cool concrete is disipating the heat fast enough that the ambient temp has only gone up 2-3* since I started using basement air to cool the lights. The AC is running slightly more now that i'm not using the colder outside air to cool the lights, but I think the increased AC use is a better alternative than condensation all over my plants.
 

kingromano

Well-Known Member
hi
i was wondering the same thing about ac in winter in a sealed room

winter here is like 30 degree farenheit, ac will work for cooling some lights? i mean 30 degree F is not too cold for outdorr unit?

i guess i need way less than 5000btu/1000w
 
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