Chiller and Return Pump

[raymondpua]

Planning for my future 3x2x2 with sump build to max the cabinet can contain. Total capacity max 400l.

Intend to use Artica 1/4hp chiller, f/rate 1800l/h - 7200l/h, capacity up to 980l. Chiller will be outside cabinet.

Option 1:

Should I have a return pump (say Eheim 1262 f/rate 3400l/h) + a pump for chiller (2000l/h) with its cooled return pointing towards the return pump intake so that hopefully the cooled water is immediately taken in by the return pump's intake. But this would mean the chiller may be cooling the already cooled water assuming the return pump did not intake all the cooled water back into the main tank, and hence probably the water temperature not constant and chiller working hard and not efficient.

Option 2:

OR should I use a 5000l/h return pump connected to chiller and have the chiller's return conncected directly to the return pipe . This would mean the cooled water is piped back to the main tank directly. This case seems better as in the cooled water is directly pumped back into the main tank and I uses 1 pump less and also increases my tank flow/hr, assuming headloss of 1500l/h(piping+chiller+elbows), to 8.5x (5000-1500 / 400).

Whaich option is better?

Regarding the chiller. I can actually use a smaller Artica, 1/5hp (f/rate 1800l/h-4800l/h, capacity 680l). Did sizing calculation and is sufficient but am thinking of the 1/4hp. Ambient temp + equipment temp etc 31C, intended temp 25C. For 1/5hp it will take about 3.2hr to cool from 31C to 25C and subsequent cooling from +1C will take about 1hr. If using the 1/4hp chiller, it probably will take half the time to cool from +1C hence less power consumped.

Am I right in this assumption or am I spending unnecessarily for a bigger chiller?

[LittleBurger]

Planning for my future 3x2x2 with sump build to max the cabinet can contain. Total capacity max 400l.

Intend to use Artica 1/4hp chiller, f/rate 1800l/h - 7200l/h, capacity up to 980l. Chiller will be outside cabinet.

Option 1:

Should I have a return pump (say Eheim 1262 f/rate 3400l/h) + a pump for chiller (2000l/h) with its cooled return pointing towards the return pump intake so that hopefully the cooled water is immediately taken in by the return pump's intake. But this would mean the chiller may be cooling the already cooled water assuming the return pump did not intake all the cooled water back into the main tank, and hence probably the water temperature not constant and chiller working hard and not efficient.

Option 2:

OR should I use a 5000l/h return pump connected to chiller and have the chiller's return conncected directly to the return pipe . This would mean the cooled water is piped back to the main tank directly. This case seems better as in the cooled water is directly pumped back into the main tank and I uses 1 pump less and also increases my tank flow/hr, assuming headloss of 1500l/h(piping+chiller+elbows), to 8.5x (5000-1500 / 400).

Whaich option is better?

Regarding the chiller. I can actually use a smaller Artica, 1/5hp (f/rate 1800l/h-4800l/h, capacity 680l). Did sizing calculation and is sufficient but am thinking of the 1/4hp. Ambient temp + equipment temp etc 31C, intended temp 25C. For 1/5hp it will take about 3.2hr to cool from 31C to 25C and subsequent cooling from +1C will take about 1hr. If using the 1/4hp chiller, it probably will take half the time to cool from +1C hence less power consumped.

Am I right in this assumption or am I spending unnecessarily for a bigger chiller?

I'm not guru but I think if the flowrate to chiller is too strong, the chiller might not have time to cool the water down. I'm using teco15 and was reading on the flowrate for chiller and found that if flowrate is too fast, chiller not enough time to contact with water and chill down, therefore consume more power. This is what I read from a blog.

[wilsontantw]

Bro, may I offer options 3 and 4..

3) from ur option 1, using 2 pumps. The chiller can return to main tank instead of going to sump. This way you have 2 returns. It provides redundancy.

4) from ur option 2, using 1 bigger pump. You can try to T-off from the return pump. One goes to main, another goes to chiller. It's important to have a control valve to the chiller to control the flow rate.

For me, I added another control valve at the return to main tank... this allows me to fully control the flow that I want.. unfortunately you don't have redundancy. If pump fails, game over.

As to which is the best, I'm not sure... I am using option 4, plus another pump T-off to FR and return... this helps me provide redundancy plus good turnover. I'm running at close to 20x...

No cookie cutter formula here, as it varies based on what you keep. hope u can find ur optimal flow.

[tropic]

Bro, may I offer options 3 and 4..

3) from ur option 1, using 2 pumps. The chiller can return to main tank instead of going to sump. This way you have 2 returns. It provides redundancy.

4) from ur option 2, using 1 bigger pump. You can try to T-off from the return pump. One goes to main, another goes to chiller. It's important to have a control valve to the chiller to control the flow rate.

For me, I added another control valve at the return to main tank... this allows me to fully control the flow that I want.. unfortunately you don't have redundancy. If pump fails, game over.

As to which is the best, I'm not sure... I am using option 4, plus another pump T-off to FR and return... this helps me provide redundancy plus good turnover. I'm running at close to 20x...

No cookie cutter formula here, as it varies based on what you keep. hope u can find ur optimal flow.

wilson..whats your tank and sump capacity?