water flow

[frodo]

just hook up a lil giant pump with 300gpm rate-ing

the outlet is 3/8 '' reduced to 1/4'' tubing.

i have flow, but am concerned about using the 1/4'' tubing

is it of sufficient size to cool a 3/4'' liebig .. 24'' long .

[NZChris]

Try working it out here http://homedistiller.org/calcs/cond_calc

[heartcut]

I run a 1" over 3/4" x 24" liebeg with 50 psig water thru 1/4" tubing, ss half keg, propane. The only time I use above 9 gph is stripping in potstill mode (my water flow meter tops out at 9gph). You should be fine but might need to run a bypass for excess flow to take it a little easier on that pump.

[ranger_ric]

The most important number in speccing out a pump is its "head" or "lift" capability. If that pump can move 300 gph that doesnt mean it can push it up 5 feet. So make sure if you are pumping off of the floor that your pump will actually lift the water as high as you need it !!

[frodo]

The most important number in speccing out a pump is its "head" or "lift" capability. If that pump can move 300 gph that doesnt mean it can push it up 5 feet. So make sure if you are pumping off of the floor that your pump will actually lift the water as high as you need it !!

it will be in a bucket less than 5' from the boiler..

[Danespirit]

It's correct that one should see on the liftheight...
Many don't realize this and buy a pump just because it has a tremendous output (Gph or Lph)..that don't necessary mean it's a good pump..!
A standart refluxstill is let's say 1500 mm, which would be the liftheight the pump has to deal with, in order to supply the refluxcondenser.
When we take your pump as an example, we can se at 1500 mm we have 100 Gph less flow.
Anyway...with your still i think your pump is more than adequate, even with a 1/4" restriction.
You can measure the flowrate by putting a hose, placed at the adequate height on your pump (with the 1/4" on) and measure how many litres pr. min flows through.
Multiply this by 60 and you have the litres pr. hour. I think there will be a lot of flow, even with the 1/4" restriction on.

[frodo]

It's correct that one should see on the liftheight...
Many don't realize this and buy a pump just because it has a tremendous output (Gph or Lph)..that don't necessary mean it's a good pump..!
A standart refluxstill is let's say 1500 mm, which would be the liftheight the pump has to deal with, in order to supply the refluxcondenser.
When we take your pump as an example, we can se at 1500 mm we have 100 Gph less flow.
Anyway...with your still i think your pump is more than adequate, even with a 1/4" restriction.
You can measure the flowrate by putting a hose, placed at the adequate height on your pump (with the 1/4" on) and measure how many litres pr. min flows through.
Multiply this by 60 and you have the litres pr. hour. I think there will be a lot of flow, even with the 1/4" restriction on.

the results were 1 liter per minute..or 60 liters per hour

[Danespirit]

...sounds strange..even with the restriction.

I just had a 1/4" fitting lying around and measured it (Ø8 mm Inside).
1 l is poured through it under 20 seconds...just by using a funnel and pouring it gently in there.
The funnel isn't even full, so no significant pressure.

How high is your output placed..?
Are there other restrictions in the flowpath..?
Have you tried running the pump just with a hose connected..?

[CR33G3R]

You did say that it is reduced to 1/4 after the pump by tubing. how hard would it be to step the tubing up from the 3/8 or even keep it there to feed the liebig.
For feeding the liebig getting hose and fittings is fairly cheap. Just an idea.

[frodo]

You did say that it is reduced to 1/4 after the pump by tubing. how hard would it be to step the tubing up from the 3/8 or even keep it there to feed the liebig.
For feeding the liebig getting hose and fittings is fairly cheap. Just an idea.

here is pump,,,i think i will up the tube to 5/8'' id

the od of the outlet is 5/8''..id is 3/8

Danaspirit...How high is your output placed..? it was even with the pot
side by side on counter
Are there other restrictions in the flowpath..? none,
Have you tried running the pump just with a hose connected..?
i submerged pump in a pot of water..shot water all over the counter
with out tubing....wife was pissed...gave me the stinkeye

[DAD300]

One liter a minute will cool Approx 3,500watts if input water is less than 80F.

[heartcut]

Centrifugal pumps will overcome outlet restrictions fairly well, but inlet restrictions (and buildup in the impeller vanes) shut them down. Your observed flowrate sounds really low.

[frodo]

Centrifugal pumps will overcome outlet restrictions fairly well, but inlet restrictions (and buildup in the impeller vanes) shut them down. Your observed flowrate sounds really low.

i agree,,,i just put it in the sink..with a 6'' tube pointed down,,,so it will not splash.

timed it at 1 gallon per minute. that equates to 60 gallons per hour. it is rated at 300 with 1' head

http://screencast.com/t/JyspDlwgQghC" onclick="window.open(this.href);return false;" rel="nofollow

[frodo]

Centrifugal pumps will overcome outlet restrictions fairly well, but inlet restrictions (and buildup in the impeller vanes) shut them down. Your observed flowrate sounds really low.

i agree,,,i just put it in the sink..with a 6'' tube pointed down,,,so it will not splash.

timed it at 1 gallon per minute. that equates to 60 gallons per hour. it is rated at 300 with 1' head

http://screencast.com/t/JyspDlwgQghC" onclick="window.open(this.href);return false;" rel="nofollow

after reading your post..i removed the impeller shroud..inspected the impeller for debree

no visable crud,,cleaned all put back together..tested in sink,,no change

1 gallon per minute...

it is old as hell,,been sitting in a shed for 20 years, collecting dust