riffraff8
Member
Hi all,
I've been running a flower tent (2' x 4' x 5' high) for about a month, and am constantly on the verge of it overheating. I've done a ton of research, built out all my fans/ductwork in the best way I can think of. yet I still constantly feel like my plants will overheat any minute I step out of the house. Here's the setup:
The tent is in a closet. The closet doors are removed, so it is very open, almost as if it were just sitting in the room. There is air conditioning in the room, and while it can occasionally get up to as high as 77F in the room, it is generally about 72-74F on average. My understanding is that with proper ventilation I should be able to keep the tent just a few degrees warmer than the room. I would be happy with a constant 80-82 in the tent, however it keeps broaching 84, even hitting 86F on occasion. That really makes me nervous for my plant's health.
The tent is run at a constant 40% RH for flower. This is maintained with a humidity sensor/controller/humidifier combo, as the room RH has been 25-30% outside the tent.
The tent is running one 600W HPS bulb, hanging about 2.5 Ft above the canopy. The ballast has a dimmer switch with settings for 50%, 75%, and 100%. As I'm having these temperature issues, I've never been able to run it on 100% (full 600W), and have been running it on 50% (a little over 300W draw) just to keep it from overheating. Even at that setting, it gets too hot too frequently for my comfort zone.
The cool tube is a 6" diameter. I have a 449CFM vortex fan hanging just outside the tent that is pushing. It pushes through about half a foot of the 6" duct work into the tent to the cool tube, through the cool tube, and out the other side of the tent. It then has about 3 more feet of the 6" ducting out the other side, with no major bends, to a window where it exhausts. That window also houses my AC unit, so the venting happens on the side next to the AC. I have this fan turned to max (the full 449 CFM), though I would love to be able to turn it down slightly on the dial for noise purposes. I have checked all the ductwork and the seams from the vortex to the window, and no air is leaking from the system.
Additionally, I have 2 carbon filters mounted to the ceiling of the tent, a 6" iPower, and a 4" iPower. The 6" does most of the filtering, the 4" is just a backup because I had it lying around. The 6" is pulled (after the carbon filter) with a 240CFM can fan, also on a dimmer but set to full. The 4" is pulled with a tiny little 100CFM can fan that barely moves any air after the drag from the filter, but does still push a little clean air. As I said this is just a backup for me, I know I shouldn't expect much from such a tiny can fan. Each of my carbon filter lines run about 2.5 - 3ft of duct work total, and vent back into the room. While their exhaust is the same temperature as the tent, they don't move enough to warrant window exhaust IMO, and don't add much to the room heat that the AC can't take care of. The tent uses passive intake through all the flaps by the floor, and does retain negative pressure nicely when I have the 240CFM can fan on full (it always is!)
Aside from all that, I have 2 small clip-on fans inside the tent that are keeping the air moving in there, and blowing between the canopy and the light.
Even with all that running on full, and my poor 600W light dimmed to ~300W with the ballast switch, I'm still seeing 75F in the room and 85F in the tent right now.
One more thing, I have a mesh bug screen on the vortex that keeps dust from collecting on my light. The bug screen does fill with dust about once or twice a week and I slurp it out with a vacuum because it does drastically reduce the vortex performance if left dusty for multiple weeks. I make sure to maintain this, as well as my AC filter at least once a week with the large volumes of air being moved.
So my question is, what gives? Why are some people able to bring their tent temps down to within just 2-3 degrees hotter than ambient? Moreso, how are they doing it with smaller inline fans and less air being moved? I've been constantly making small improvements as I notice issues, but at this point I don't see any obvious change I can make to get the temp to drop those 5-6 precious degrees. I will say that when I was running this as a veg tent with far higher humidity for young growth (60-70%RH), I was able to keep the temp no higher than 82F. Of course this is a function of the humidity, so having a dryer 40% for flowering does mean a hotter tent. I'm hoping that someone has advice or improvements that will help counteract the higher temps. Thanks!
I've been running a flower tent (2' x 4' x 5' high) for about a month, and am constantly on the verge of it overheating. I've done a ton of research, built out all my fans/ductwork in the best way I can think of. yet I still constantly feel like my plants will overheat any minute I step out of the house. Here's the setup:
The tent is in a closet. The closet doors are removed, so it is very open, almost as if it were just sitting in the room. There is air conditioning in the room, and while it can occasionally get up to as high as 77F in the room, it is generally about 72-74F on average. My understanding is that with proper ventilation I should be able to keep the tent just a few degrees warmer than the room. I would be happy with a constant 80-82 in the tent, however it keeps broaching 84, even hitting 86F on occasion. That really makes me nervous for my plant's health.
The tent is run at a constant 40% RH for flower. This is maintained with a humidity sensor/controller/humidifier combo, as the room RH has been 25-30% outside the tent.
The tent is running one 600W HPS bulb, hanging about 2.5 Ft above the canopy. The ballast has a dimmer switch with settings for 50%, 75%, and 100%. As I'm having these temperature issues, I've never been able to run it on 100% (full 600W), and have been running it on 50% (a little over 300W draw) just to keep it from overheating. Even at that setting, it gets too hot too frequently for my comfort zone.
The cool tube is a 6" diameter. I have a 449CFM vortex fan hanging just outside the tent that is pushing. It pushes through about half a foot of the 6" duct work into the tent to the cool tube, through the cool tube, and out the other side of the tent. It then has about 3 more feet of the 6" ducting out the other side, with no major bends, to a window where it exhausts. That window also houses my AC unit, so the venting happens on the side next to the AC. I have this fan turned to max (the full 449 CFM), though I would love to be able to turn it down slightly on the dial for noise purposes. I have checked all the ductwork and the seams from the vortex to the window, and no air is leaking from the system.
Additionally, I have 2 carbon filters mounted to the ceiling of the tent, a 6" iPower, and a 4" iPower. The 6" does most of the filtering, the 4" is just a backup because I had it lying around. The 6" is pulled (after the carbon filter) with a 240CFM can fan, also on a dimmer but set to full. The 4" is pulled with a tiny little 100CFM can fan that barely moves any air after the drag from the filter, but does still push a little clean air. As I said this is just a backup for me, I know I shouldn't expect much from such a tiny can fan. Each of my carbon filter lines run about 2.5 - 3ft of duct work total, and vent back into the room. While their exhaust is the same temperature as the tent, they don't move enough to warrant window exhaust IMO, and don't add much to the room heat that the AC can't take care of. The tent uses passive intake through all the flaps by the floor, and does retain negative pressure nicely when I have the 240CFM can fan on full (it always is!)
Aside from all that, I have 2 small clip-on fans inside the tent that are keeping the air moving in there, and blowing between the canopy and the light.
Even with all that running on full, and my poor 600W light dimmed to ~300W with the ballast switch, I'm still seeing 75F in the room and 85F in the tent right now.
One more thing, I have a mesh bug screen on the vortex that keeps dust from collecting on my light. The bug screen does fill with dust about once or twice a week and I slurp it out with a vacuum because it does drastically reduce the vortex performance if left dusty for multiple weeks. I make sure to maintain this, as well as my AC filter at least once a week with the large volumes of air being moved.
So my question is, what gives? Why are some people able to bring their tent temps down to within just 2-3 degrees hotter than ambient? Moreso, how are they doing it with smaller inline fans and less air being moved? I've been constantly making small improvements as I notice issues, but at this point I don't see any obvious change I can make to get the temp to drop those 5-6 precious degrees. I will say that when I was running this as a veg tent with far higher humidity for young growth (60-70%RH), I was able to keep the temp no higher than 82F. Of course this is a function of the humidity, so having a dryer 40% for flowering does mean a hotter tent. I'm hoping that someone has advice or improvements that will help counteract the higher temps. Thanks!
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