Is too much flow from a pump bad?

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smokinghole

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I'm looking at finally getting a pump for myself. I am eyeing a Little Giant 4-MD-HC. My main question is with the flow rate near 14gpm is there a problem with throttling back the flow rate using a ball valve (if I need to)? I plan on using this for pushing hot liquor (tired of lifting hot water), then whirlpooling, and cooling. My intent is to hopefully have a very good whirlpool, better than the videos I've seen using the 3-MD-HCs. I like overkill as long as overkill isn't detrimental. I hate buying something more than once so I'd like to get a little more than I need now so I can grow in the future. I currently brew 6-12 gal batches.

I have pretty much ruled out Chugger pumps, and March pumps. I've read too many gripes about priming and or failures using those pumps. I have yet to find a "my little giant doesn't prime" or my "little giant died on me in the middle of a brew". So spending a little extra for a bigger pump with a better rep for durability is right up my alley.
 
Throttling down that 1" intake is something I wonder about. I wonder how it would handle a typical 1/2" inlet. If you test it please report the results.
 
iaefebs said:
Throttling down that 1" intake is something I wonder about. I wonder how it would handle a typical 1/2" inlet. If you test it please report the results.

Exactly. You should probably have a valve on your kettle (and run tubing) that is 1 inch ID if you were to go this route. I use the standard march pump that everyone else has, and it works fine for my 10 to 30 gallon batches. All my tubing and valves are 1/2" ID or greater, and this prevents me from cavitating.
 
I'm glad I posted this up because it made me think of aspects I was neglecting. Those aspects being 1" ball valves which would add $100 at $50 a piece. Then the hosing and other fittings. I think I might just go back down to the 3-MD model since my kettle is currently set up with 1/2 in stuff already. If I was starting with a blank kettle I might go this route but if running the proper diameter hosing gives you good enough performance on 30 gal batches I'll just buy the "small" pump.
 
Proper pump design is to have just enough power for your most taxing process (probably cleaning). Having too much flow reduces the precision you can throttle to. Ie if you are running at 25% flow you have to make way smaller adjustments than if you are at 75% capacity for the same flow rate.
 
Well after a couple weeks of deliberation I ordered a 3-MD-HC instead of the 4. It was about $50 less had better performance than the standard style brewing pump. I didn't have to change my kettle valve. Thanks for the insight guys!
 
I have the pump already. Damn PEXuniverse.com is quick. Then again I am only a state away but I have heard horror stories of places taking forever to ship.

I will report back how it performs possibly this weekend if I can get some fittings to use on the pump.
 
So this is how I built around my pump. I did my best to keep a 3/4" supply for the inlet. Then I tried to keep a true 1/2" output which I know wasn't as important as the inlet. I ordered fittings from Grainger that are 3/4" for a 1" ID hose. It gives me about .800" of flow to the hose so that was my avoidance to restriction. Then the same fitting goes on the pump with the 1" hose. The outlet is running 5/8" ID hose and the fittings were 1/2 female NPT to 5/8" barb.

I fired it up after installing the 3/4" valve on the pot and beyond needing better hose clamps to seal up the system it works beautifully. I think this thing will get a pretty killer whirlpool going.
 
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