Why do we assume a large return pump is needed?

[hahnmeister]

<a href=showthread.php?s=&postid=9976039#post9976039 target=_blank>Originally posted</a> by DarG
Running the chiller on the closed loop you are still adding heat from the closed loop pump just as you would by sizing the sump return pump to be within the chillers flow specs. I understand the low flow idea but sometimes there are tradeoffs and one has to make choices. my tank is not drilled to and hanging multiple pipes for closed loop flow was a less appealing option for me than using in tank prop pumps.

Ah, but you are not incurring a huge head loss from the sump return having to pump through that extra length of chiller. FWIW, a drop in chiller would eliminate the problem all together too. The main idea is just to keep the chiller off the same line as the sump return. The sump return is best if it just has a straight shot up to the tank above, only one elbow or two, and minimal pipe restrictions. You can use a MJ1200 to feed a chiller for a mere 10-12 watts on a closed loop and incur minimal heat. If that chiller were to be used on the sump return line, it would use up more than double that wattage in head-loss from the pump.

Since I started this article way back when (when I was Herbert T. Kornfeld), I am pleased to say that this method has cought on in popularity. Stream style pumps have gained a larger place in the market, as have lower flow sump returns, direct fed recirc skimmers, etc. Maybe its partly due to the rising attention being given to energy conservation in the states, maybe its all the Euro mfg's that are importing and showing their influences. Either way, its a good thing.

 

[jnarowe]

I really liked the name Kornfeld!

 

[RGibson]

<a href=showthread.php?s=&postid=9977601#post9977601 target=_blank>Originally posted</a> by jnarowe
I really liked the name Kornfeld!

so did i.