cooling setup advice?

[bradsgonetrekkin]

I got a neat little 240v plug in submersible pump from Bunnings the other day they were getting rid of for $20 to make way for new stock.
The specs are:-
- 250w
- Max flow rate 6000litres/hour (100litres per min)
- Max submergence 5m
- Max head 6m
- Max operating pressure 0.6 bar, 8.5 PSI, 0.06 MPA
It made short work of transferring 70 odd litres of wash from the fermenter into the still. Better than the pipe sucking and bucket bailing I used to do....
Now I’m going to have a play around to see if I can get it to work to recirculate cooling water to the stills via a couple of tanks.
So far I have a 200 odd litre drum and a 400 odd litre tank.
I’m still not exactly sure the final placement of the tanks but initially I’ll be putting them inside the shed within a couple of metres of the still.
I was looking at having the 200 litre drum as the coolant return point from the condensers, with a simple overflow pipe near the top to transfer the water to the lid of the 400 litre tank (its a bit lower than the 200 litre drum proposed overflow pipe). The pump I was going to insert into the other end of the bigger tank through the access lid. The pot still condenser will be just above the pump level, and the top of the vm column is around 2.65m above ground.
I haven’t got much of a clue about pumps, pressure losses etc.
I have researched a few posts on recirculation systems for cooling but still have questions:-
- Will this pump be powerful enough for the job?
- My reflux coil I made out of ¼ inch copper, is it worth trying with the pump system or should I rebuild a ¾ coldfinger with 3/8 coil instead?
- Can you use standard garden hoses in the system and still get the flow right?
- Do you need to have backpressure lines and valves to make this work properly?
- How hot does the water normally get for stripping v spirit/vm runs? This pump has some sort of thermal cut out if the transfer liquid gets too hot...

[stubbydrainer]

not knowing that particular pump I forward this info
The pump should be well capable of running the whole system based on those specs
I figure it to be one that has a visible impeller ( under guards of course ) a bit like the old Holden red motors, they are not a positive displacement pump.
A 1/4" coil would however " back-up " the water flow( maybe causing the pump to have some form of cavitation), and the line for the coil would be better off a " T " with the other hose from the "T" having a tap on the end of it to create some pressure in the line, then work your condenser as per normal with the existing valve
Normal garden hoses will do the job for ya , as for temp issues , ya just gunna havta suck it and see :laughing-rolling: :laughing-rolling:

[Kimbo]

as Draino said,
i have a similar one i chuck in my pool, it works great thru my shotgun on my pot still,
it struggles a bit thru my 1/4" double helix (tho my 1/4" tube is 6m long)
i use garden hoses. the bigger the hose the better it will work (they dont have a lot of torque)
i recon they're great, i just need to make a bigger diameter coil ;-)

[maheel]

i dont reckon it will get hot

but i run a submersible sucking from the bottom and let the "hot" return just flow onto the top of my 2000L (?) tank
this way the hot water should stay at the top... but i reckon that it circulates it all pretty quick so it hardly matters and it does not get hot

i now prefer 3/8 so my pump does not labor, but mine is a "larger" pond pump not like yours


some basic pump theory as i under stand it (limited understanding)

if your pump is in the bottom of a 1m tank and the hose comes out the top of the tank
the hose is "full" to the top of the tank water and you calculate head height from the surface of the water
not from where the pump is sitting

the theory also goes if you submerge the return line you have a closed system and the weight of the water "falling" down the return helps suck it up the intake like a siphon

[MacStill]

Stubbs is right, you will need a relief line so the pump isnt working too hard, well I think that's what he's getting at :lol:

A cold finger such as 5Star builds would be ideal in your situation though ;-)

[R-sole]

I'm doing the same think you're proposing with a much smaller pump except backwards.

I have a 500l tank outside the shed fed with rain water. The feed from the bottom of the tank goes through the wall and into the bottom of a blue 200l drum that is raised to be 2/3rd full when the tank is full. My 360 gph bilge pumps are in the blue drum.

Hot water goes back through the wall into the top of the rain water tank.

coolant2.jpg

coolant3.jpg

[bradsgonetrekkin]

Thanks for the tips guys, will let you know how it goes.