phillipchristian
New Member
If you get your chiller dialed in and sized correctly it would reduce your electricity costs by about 10% as opposed to a mini split. The bad news is that at 8k watts you would need a larger chiller than 2hp. Remember that formula is only in addition to your ambient cooling. Just assuming you have have 8k in a 10'x20'x8' room. You would need 2hp of chilling just to cool the lights. You would also have to cool the room, the exhaust from your dehumidifier, any ballasts you have in the room, and the exhaust from your Co2 generator. So lets say you have your digital ballast in the room, a 70 pint dehumidifier (that isn't water cooled), and a Co2 system (that isn't water cooled).I am seriously entertaining the idea of setting up a recirculation cooling system again since I already have all the piping needed and probably an adequate reservoir. The only issue I have is the price on a chiller that would fit my needs for over 5k watts. I am also considering stepping up to a 8k system in the future so I should probably size appropriately. If I use the rule of a 1/4 hp for each 1k light then that would require a 2 hp chiller that would cost more than a mini-split sized appropriately. I can see if you use geothermal cooling that the efficiency would go up considerably, but if planning just to use the chiller for cooling is it really any more efficient than a mini-split? I understand all the other advantages over using water vs refrigerant, but if power bill and up front cost are all that matter I am still on the fence.
-32,000btu to cool your lamps
-20,000btu of cooling for your ballasts (this is really about half if you are using the new ballast models that run much cooler). So let's say 10,000btu
-8000btu to cool the ambient temperature or space of the room.
-2100btu to cool the exhaust given off by your dehumidifier.
-4000btu to cool the exhaust given off by your Co2.
So basically you would need 66,000btu of cooling. A 5hp chiller. This is a rough guideline but it is always better to oversize these systems. Also, everyones room is different and everyones climate is different. Guys growing in cold basements may not need all this. This is from my experience in a very warm climate. It's not cheap by any means but for me it definitely was worth it. I had 2 24,000btu mini splits in my room and it wasn't doing the trick. I started water cooling my equipment (Co2 generator, Nutrient reservoir, etc.) and I purchased a 5 ton air handler and ducted my lights back to its return. My room is perfect right now and has been for 2 years.