Chiller questions

[meschaefer]

Would you believe how hard it is to find information on chillers? And I could really use some help thinking about this.

I have a 220 gallon tank, with a 120 gallon sump. I figure that the total system volume has to be around a 250+ gallons.

The first question I have is about the difference between "in-line" and "drop in" . Which is better, and by better I mean more efficient. In comparing models from the same company, it looks like the in-line models use less energy, but they need a feed pump. That being said I think I can feed the chiller from my return pump. Is there any other reason you would want a "drop in" chiller over a "in-line"?


The second questions is also about efficiency. As said I have about 250+ gallons of water. According to manufacture specs the Tradewind 1/3hp will handle 300 gallons, while the 1/2hp will handle 450 gallons. I have read that by buying a larger chiller than I "need", that it will cool faster and as a result run for a shorter period of time saving energy. Is this true? Do i really want the 1/2hp, over the 1/3hp? The upfront cost is a somewhat secondary concern (secondary to power consumption), but I could use the savings someplace else on my system (did someone say calcium reactor?)


The final question, is about particular models. The Tradewinds get good word of mouth. I have also been looking at the Pacific Coast chillers and the prime modular chillers. I have about $1,000 to spend on the tank (birthday presents to myself), but I also don't feel a need to spend the entire sum on a chiller.

Any recommendations? experiences with chillers? ....????

 

[tbittner]

Sizing depends on the temperature swing of the water. If it only swings three degrees then a smaller chiller won't have any problem keeping the temp down. I'm not sure on the energy consumption question though. I don't know if a larger chiller will actually use less electric.

Most chillers won't handle the amount of flow we have from our return pumps. It's too fast. You could plumb off a T and ball valve it to control the amount of water flowing through the chiller though. But then you'll be taking away from the flow through your tank. I use a small submerged pump to pump water through the chiller and it works fine. I have 570g in my system and a 1/3 hp teco chiller keeps the swings within a degree. But most of this water is in my basement so it's cooler down there anyway.

 

[meschaefer]

<a href=showthread.php?s=&postid=12494459#post12494459 target=_blank>Originally posted</a> by tbittner
Sizing depends on the temperature swing of the water. If it only swings three degrees then a smaller chiller won't have any problem keeping the temp down. I'm not sure on the energy consumption question though. I don't know if a larger chiller will actually use less electric.

Most chillers won't handle the amount of flow we have from our return pumps. It's too fast. You could plumb off a T and ball valve it to control the amount of water flowing through the chiller though. But then you'll be taking away from the flow through your tank. I use a small submerged pump to pump water through the chiller and it works fine. I have 570g in my system and a 1/3 hp teco chiller keeps the swings within a degree. But most of this water is in my basement so it's cooler down there anyway.

Not sure about the overall swing, as this will be the first summer with the tank. It could be large. Although the tank is in my basement, it is not a really basement, only half is below grade. It is slightly cooler than the rest of the house, but for the fact that it is not air conditioned down their. Also, I need to be prepared for 100 degree days in August.

I already have the T and ball valve covered. I run a reeflo dart into a manifold and run phosban and occasionally carbon from it. I don't really use the return pump for flow in tank, I have vortechs and tunze for that, so I am not concerned about siphoning off water flow through the DT.