Return Pump Help

[goldie1]

Hello RC

I need some help trying to determine what return pump to use for my JBJ 1/5HP Chiller. I tested the chiller with a mag 9.5 and was only getting 350 gph roughly. Thats just at the outlet of the chiller. Thats my ideal return rate at the DT. But i have roughly 6 ft of head loss after the chiller before the DT. JBJ recommends between 480/1320 gph. I really wanted to run the return pump to the chiller then back to the tank. I am dealing with roughly 6ft of head from the sump to the tank. I guess maybe it's time for an external pump? Maybe just run the chiller back to the sump? I'll still need another pump even with that route. :headwalls: I believe thats not as efficient maybe. How many gph should i be looking for @ what max head roughly? I really dont want to continue buying pumps that aren't going to work.

 

[minix4242]

I'm no expert, but I did stay in a Holiday Inn last night (and I have a danner mag 9.5). They run warm to begin with (when pumping 700+gph), I would imagine they run even hotter with restricting plumbing like that. Wouldn't that negate the effects of the chiller?

Personally, I'd try to reduce the added electrical expense of the chiller and get a decent external pump that won't impart even more heat into your system. OR... The mag should give you 650gph? to your DT if you eliminate the restrictions, and then you could use another pump for the chiller.

NEVERMIND--- Wait, check the Specs of the chiller. From what I just read you only need 8-22gph through the chiller? Just get a little utility pump for the chiller and run it back to your sump.

edit: ignore the above, I just reread and you were right... it's 8-22g/minute which is the 480-1320gph you originally stated.

 

[Worom]

I believe the mag 9 is the recommended rtrn pump per jbj. Those flow rates 480/1320 GPH have a huge variation. The mags run really hot when restricted like minix4242 said. Others may chime in but I think your right you kinda have two options.

1. Run an external maybe an Iwaki 40-50 series. Should be able to run a chiller and handle your return. Something that has a high max head rtng, i.e. 20ft mx head.

2. Run a external to reduce heat as just a return pump maybe Iwaki 20 series. Then run a separate pump for the chiller back to the sump. You will probably loose 300-400gph through the chiller alone. Just count your wattage when choosing 1 vs 2 pumps.

Hope this helps somewhat

 

[goldie1]

Thanks guys for your help.

So i assume if i ran a dedicated pump for the chiller and my goal is roughly 700 gph - 900 gph at the output of the chiller, I would want to choose a pump that pushes around 1000 gph - 1300 gph? And a max head somewhere around 15ft-20ft?

I tested the mag 9.5 straight up, no chiller with about 2 ft of vinyl tubing Max 3/4 and its only pushing 650 roughly. I used a 5 gallon bucket and let if overflow outside. Thought they were rated for 950 gph. I only had two feet of head tops I used a head loss calculator and got these results. Total losses are 4.13 feet of head pressure, or 1.78 PSI. with a flow rate of 810 GPH. Process took 103 iterations.

So i will move away from the mag 9.5. I looked into the iwaki's, they can really push some serious flow. I assume this pump would be ideal to run just the chiller?

Iwaki MD-40RT
156W
822 GPH
21.3 ft Max Head

Its appears a little low on the flow side but assume it will be made up with the max head?

Any other pump recommendations for the chiller?

Good thing all my other equipment uses super low wattage. :celeb2: