We have the 1.5hp model. We use it to cool an 8×8 hot tub for summer. Our tub has 490 gallons. In the hottest months it does take a little while to get the temp in the whole tub to start coming down. I’d say when outside temps are at 100 or more, it would cool our tub about 3degrees per hour. Putting the unit in the shade defiantly helps. When temps are in the low 90s it cools much faster more like 5-7 degrees per hour. We didn’t keep ours on all the time, although you could leave it on and the cooler will cycle to maintain your desired temp. It does pull 1300 watts through a 110 outlet, the lights inside on that circuit noticeably dim when it cycles to start cooling. I read some reviews that the fittings are not standard and I’ll agree with that they are defiantly not standard, I did break one off. They can be found in the internet, and a fitting kit is not that expensive I bought 2 additional kits in case I need another.