Winter Cooling: Variable Speed Window AC vs Chiller/Ice Box

[Mota French]

Hello everyone. Long time lurker here who finally started posting. My fundamental question is in regard to running a pair of the new LG 22k BTU window ACs during the winter in the SE USA. In the past, I’ve cooled my room (20’ x 14’) with only one of the old 24k BTU window ACs. This has been no problem for 10 months of the year, but for the coldest 2 months I had the same problem others do with the unit face/intake freezing and the fan blades inside attaching to frozen water in the drain pan, resulting in a very loud noise. However I have recently purchased some new tech: a pair of LG LW2217IVSM window air conditioners that have not only dual-inverter compressors but also VARIABLE SPEED, which I’m hoping will enable me to use these new ACs during the winter (daytime only).

I’m really hoping this option works for me, because if it doesn’t then my only other option for effective winter cooling is with a complete water cooling system that I acquired as a plan b. With this, the chillers/reservoir/pump/exhaust fans would be installed in the unfinished dirt basement directly below my grow room (8’ ceiling); then the flexible PVC hoses would be ran through the floor and connected to the mainifolds/Ice Boxes/exhaust fans above in the grow room itself. This system consists of 4 x 1.5 HP Commercial Water Chiller, a pair of 55g drums, each with a 1 HP Flotech cast-iron inline pump, 8 x 8” Ice Boxes, 4 x 8” inline fans, several additional 8” inline fans for moving hot air discharge from the chillers from the lower basement to outside, quite a bit of 1” and 1.25” flexible PVC (spa hose), and a few feet of the red & blue .5” rubber hoses. The main thing I dislike about the Water-Cooled system is that it would require me drilling into the floor of the grow room: a pair of 1” holes for supply water and a second pair of 1.25” holes for the return water. As I said, I really DON’T want to drill those four holes in the floor…

I would greatly appreciate any knowledgeable replies regarding which of these options would be best for me. As I said, I already have possession of all the gear for either option, so that’s not a problem. If I chose plan a with 2 window ACs, they would only be running from 7am to 7pm, when the max AVERAGE high temperature outdoors is in the 50s (F). As for the 7pm to 7am time, when the AVERAGE low temperature is in the low 30s (F), I wouldn’t expect the window ACs to run hardly at all because it’s nighttime in the grow room and the only source of heat load then would be the 70 pint dehumidifiers I use too keep nighttime humidity in the room acceptably low.

Thanks again for any window AC help anyone might offer. I found some useful info in this thread:

https://www.rollitup.org/t/window-air-conditioner-freezing-up-will-portable-ac-do-the-same.953260/page-2

In fact, I attempted to start a conversation with one of the long time members on that thread who seemed to be very knowledgeable about AC tech, but since I’ve only just started posting it would not allow me to send them a DM. :/

Also, if anyone has any questions regarding the Under Current system, or just RDWC in general I would be more than happy to answer them for you. I have 26 consecutive UC cycles under my belt, so feel free to ask if you need.

 

[ChrispyCritter]

Hi @Mota French. Both of your setups sound awesome, but I'm a fan of The water cooler option. I ran a small version for several years before my chiller died and I can't afford a new one. I used 2 8 inch iceboxes one 8 vortex s, a gh pump and a 55 gallon drum. Totally cooled the room and my co2 burner. Completely sealed too. Now I'm trying a dial hose a\c and trying to set up ventilation for it. I wish I had another chiller. It was perfectly coordinated with a controllsr, and it was really efficient too. A dehuey and heater are all linked to the system. Just set it and let it go. Good luck on your choice. You are the man with all your stuff. Peace.

 

[Mota French]

Hi there ChrispyCritter. Hope you’re doing well, and I appreciate your reply. Thanks for sharing your positive experience regarding use of the Ice Box/Vortex option. I have mine configured similarly: a 8” Vortex (actually I think my inline fans are Hurricane) in each corner of the room with a pair of 8” Ice Boxes attached to each. After all my preliminary research I didn’t expect to have any problems with the Ice Boxes, as they’re just heat exhangers… kind of like little radiators. So long as you match the heat load of your room with combined cooling capacity of the chiller(s) that will be attached to the Ice Boxes one should have no problems.

For me the problem would be having to drill 4 holes in the floor with a hole saw, as well as a larger 5th hole to enable me to run the corded thermostats on each chiller back up through the floor so that all the chillers could be controlled from inside the room itself.

I was also a bit concerned about the issue of condensation. With my setup I would end up having a total of over 100 feet of 1”/1.25” flex PVC inside the room. Since the room is relatively warm/humid (I follow VPD theory) and all the PVC is has chilled water running through them 24/7, I expect they would “sweat” a lot. I was hoping to minimize this condensation by raising the temp of the cooling solution as high as I could without negating the cooling effects of the system, as that’s the primary objective of all of this.

I will mention that I was mildly distressed when I just saw that Hydrobuilder put all the Ice Boxes on clearance, and when I saw that the original company Hydro Innovations was bought out by a larger company named Surna. Surna doesn’t seem to be as good for simple hobbyist gardeners as they are for large well-financed retailers, but I could be wrong about that.

Can I ask what type of water chiller(s) were you using for your application? Mine are the Commercial Grade EcoPlus 1.5 HP ones; four of them for 6 HP combined chiller capacity. Thanks again and take care.

 

[Renfro]

owever I have recently purchased some new tech: a pair of LG LW2217IVSM window air conditioners that have not only dual-inverter compressors but also VARIABLE SPEED, which I’m hoping will enable me to use these new ACs during the winter (daytime only).

Are they rated low ambient? If so what temp?

 

[Mota French]

Hello Renfro; hope you’re well. I’m not sure if they’re rated for a specific low ambient temperature, per se. The manufacturer’s specs can be found at:

https://www.lg.com/us/air-conditioners/lg-LW2217IVSM

My understanding is that variable speed compressors (which this unit does use) will maintain the head pressure on the unit as a result of reducing the speed of the condensing fan. It seems that this feature would make these type of window ACs better for cold ambient temperatures. I’ll know for sure soon enough, but in the meantime I was trying to be a bit proactive (instead of reactive) about this problem, as well as to increase my knowledge of AC tech in general.

 

[ChrispyCritter]

My chiller is the eco plus commercial 1 hp. I did alot of research and math (not easy for this guy lol) before I bought my stuff. I even talked on the phone to people at hydro innovations (pre_surna) and they were helpful. My chiller was a "reconditioned" deal I got on fleabay. I have tried to get it repaired locally but refrigeration specialists aren't interested and any warranty of there was one is expired. it runs but the compressor doesn't kick on. Grrrr. I know what you mean about the holes but I think water cooling or a mini sp!it are the least intrusive options, and for stealth you can't beat Indoor chillers. I was worried about condensation, but if you keep your water 20 degrees or less colder than your room (generally) it shouldn't sweat. Consider dew points and temp etc. But that is what hydro innovations told me and it worked for me. i keep my room at 84 degrees for co2 and I have a dehumidifier in the room too st for 60. I'm sure you do also but set for yourchoice. If so you're golden. I loved my setup and I'm anxious about my change to a\c since I runco2. Plus I hate change in general since I'm a grouchy old man. I have to run some kids off my lawn now.

 

[kahoona]

hi guys. im a refrigeration mechanic and id say those ac units will do nicely. if they have head pressure control on the cond fans to maintain head pressure then it should be good to 0 degrees C. there is a module you can buy to do the same thing on any window shaker. its called a headmaster. its made by carrier i believe. hope that helps.

 

[Mota French]

hi guys. im a refrigeration mechanic and id say those ac units will do nicely. if they have head pressure control on the cond fans to maintain head pressure then it should be good to 0 degrees C. there is a module you can buy to do the same thing on any window shaker. its called a headmaster. its made by carrier i believe. hope that helps.

Hi Kahoona. Thanks a lot for the information. I was unfamiliar with the headmaster module you mentioned. Hopefully two variable speed window shakers only running during daytime will suffice (without sounding like loud helicopter blades). However, I am very grateful that I can fall back on either that module or the other water-cooled system if the new variable ACs don't work out as I'd hoped. Take care and thanks again for the info mate.

I love it that we can visit these forums and become more knowledgeable about subject(s) that are very relevant to what we're doing irl. BTW, if anyone has any questions about RDWC or the UC system, specifically the new updated (2019) system, please feel free to ask, even if it's in a more appropriate thread. In the process of getting both the old and new UC systems dialed in I learned a great deal remedying my mistakes and would be happy to share the information with anyone on this forum that is interested. Happy Holidaze....

 

[TheWizZ]

Hello everyone. Long time lurker here who finally started posting. My fundamental question is in regard to running a pair of the new LG 22k BTU window ACs during the winter in the SE USA. In the past, I’ve cooled my room (20’ x 14’) with only one of the old 24k BTU window ACs. This has been no problem for 10 months of the year, but for the coldest 2 months I had the same problem others do with the unit face/intake freezing and the fan blades inside attaching to frozen water in the drain pan, resulting in a very loud noise. However I have recently purchased some new tech: a pair of LG LW2217IVSM window air conditioners that have not only dual-inverter compressors but also VARIABLE SPEED, which I’m hoping will enable me to use these new ACs during the winter (daytime only).

I’m really hoping this option works for me, because if it doesn’t then my only other option for effective winter cooling is with a complete water cooling system that I acquired as a plan b. With this, the chillers/reservoir/pump/exhaust fans would be installed in the unfinished dirt basement directly below my grow room (8’ ceiling); then the flexible PVC hoses would be ran through the floor and connected to the mainifolds/Ice Boxes/exhaust fans above in the grow room itself. This system consists of 4 x 1.5 HP Commercial Water Chiller, a pair of 55g drums, each with a 1 HP Flotech cast-iron inline pump, 8 x 8” Ice Boxes, 4 x 8” inline fans, several additional 8” inline fans for moving hot air discharge from the chillers from the lower basement to outside, quite a bit of 1” and 1.25” flexible PVC (spa hose), and a few feet of the red & blue .5” rubber hoses. The main thing I dislike about the Water-Cooled system is that it would require me drilling into the floor of the grow room: a pair of 1” holes for supply water and a second pair of 1.25” holes for the return water. As I said, I really DON’T want to drill those four holes in the floor…

I would greatly appreciate any knowledgeable replies regarding which of these options would be best for me. As I said, I already have possession of all the gear for either option, so that’s not a problem. If I chose plan a with 2 window ACs, they would only be running from 7am to 7pm, when the max AVERAGE high temperature outdoors is in the 50s (F). As for the 7pm to 7am time, when the AVERAGE low temperature is in the low 30s (F), I wouldn’t expect the window ACs to run hardly at all because it’s nighttime in the grow room and the only source of heat load then would be the 70 pint dehumidifiers I use too keep nighttime humidity in the room acceptably low.

Thanks again for any window AC help anyone might offer. I found some useful info in this thread:

https://www.rollitup.org/t/window-air-conditioner-freezing-up-will-portable-ac-do-the-same.953260/page-2

In fact, I attempted to start a conversation with one of the long time members on that thread who seemed to be very knowledgeable about AC tech, but since I’ve only just started posting it would not allow me to send them a DM. :/

Also, if anyone has any questions regarding the Under Current system, or just RDWC in general I would be more than happy to answer them for you. I have 26 consecutive UC cycles under my belt, so feel free to ask if you need.

You need fan cycle switch installed to keep the highside pressure from dropping too low. The room also needs to have a load while running the cooling(which I’m assuming isn’t an issue). A head master control will work too.

 

[TheWizZ]

You need fan cycle switch installed to keep the highside pressure from dropping too low. The room also needs to have a load while running the cooling(which I’m assuming isn’t an issue). A head master control will work too.

I just read that the new window units have variable speed compressor and fans, youll be good with that.

 

[Mota French]

Hi TheWizZ. Thanks for your reply. Yeah, I've decided to roll with the 2 variable speed window ACs during the winter cycle. Everyone I've spoken to on the subject agrees that the variable speed compressor fans on these particular window ACs should work just fine... and if it ends up not working out then I can fall back on the full water-cooled system mentioned above. Thanks again and take care.