Convoluted? Cfcw Questions...

[Trent]

Gday all
After much reading of CFCW posts, I have deduced that gravity fed chillers are fine, so I am gonna have a go at making one, but I have a few questions. First up, is 1/2" OD too big? I know it wont fit a regualr garden hose around it, maybe I could get a 5/8" ID hose instead? 2nd of all, my current immersion is about 18m long, is that too long for a gravity fed chiller? I am happy enough to cut it down, but dont want to if I dont need to, obviously. I have a pre chiller of about 10m that I will be using anyway, so the water going into the chiller will be reasonably cold. Finally, what the hell is convoluted? Do I have to crimp my tubing to create turbulence, especially at that length? I am using WAY too much water to chill right now, and it is taking at least an hour, usually more, and I can only get the wort down to about 28C, so I think CF is the way to go. Any answers will be much appreciated, and I will be off to Bunnings or similar this weekend to get all the bits and pieces needed.
All the best
Trent
PS I will probably be getting a pump to run it eventually, but right now, it aint in the budget.

 

[big d]

in a computer access way without an internal pic trent convoluted pipe looks like this.../\/\/\/\/\/\/\/\/\...kinda like an internal spiral in the pipe.it increases the contact surface area of the hot wort to the cooling of the water going in the opposite direction.
1/2 " isnt to big providing you can fit your hose over it.i think most hose(garden variety) is 3/8".
a few of us do the pre-chiller bit by having a coil going through an ice bath before going into the wort due to our location and hot water mains temps.
a search on ahb or goggle may help even more.( pics )

cheers
big d

 

[GMK]

i think the inside pipe should be smaller than 1/2" - this will give a greater surface area to volume ratio and therefore greter cooling efficiency.
BrewGoliath sell a CFWC kit - copper tube, hose and fittings for under 100.00.

The convoluted CFWC are 120.00 USD plus freight from more beer.

Hope this helps

 

[Trent]

Thanks for the replies guys
I now understand what a convoluted chiller does, your little computer animation made sense to me, Big D! I can understand that smaller than 1/2" would be better for chilling, but seeings as I have heaps of 1/2", and I dont really have the cash for some more tubing, I will just see how I go with that. Does anyone know if I should crimp the tube if using gravity, or does that go the same for pumping? Is this going to give the same effect as convolution? And also, reading about the gravity fed ones that dont chill too much because of thermodynamics of some sort (forget what it was called), because of slow flow, I am worried it may happen to me, being my tubing is so long. I just wanna get it right the first time.
Cheers
Trent
EDIT - I just re-measured my tubing and it MAY be 3/8" :huh: . It looks about 11.5mm OD, and I can just fit a garden hose onto it. I thought 3/8 is about 9mm. Maybe I need to go back to school!

 

[Screwtop]

It's all about OD's and ID's. Easy enough to buy larger ID hose for water jacket. Don't think crimping is going to do much as it wouldn't add length/surface area. To describe convoluted, concertina'd but rounded. Imagine a length of pipe that has been hit up the arse :lol: :lol: I think the convolutions would also provide turbulence and improve effeciency. Pitty it does not work in reverse as it is easy enough to buy convoluted electrical conduit which could be used for the water jacket, thinking about it, it probably would increase effeciency by a poofteenth depending on the rate of flow of the water. RAVE RAVE

 

[Crazy]

While down in Tassie a few years ago working at Cascade, I did a trip with my wife up to Cradle mountain. While up there we went to a tiny little winery which looked like a house with a stone shed and a few grapes in the garden.

I got talking to the owner about on of his vessels ( a dimple jacketed stainless thing that he paid next to nothing for at an auction). I don't think he gets many visitors that are interested in the process and so I ended up spending quite a few hours talking about the industry.

It turned out he started a company many years ago making counterflow chillers which ended up becoming one of the popular types used in both wine and beer and other industries. He showed me one of the sections and they were realy quite simple. The inner stainless tube (wort) has a 'thred' rolled into it and the outer also has a tred but this time in the opposite direction. Apperantly this movement greatly increased cooling from just straite tube. Each section was from memory about 3m long and there would be banks of them all on a rack. If extra cooling was required you just put more peices in series.

I know a bit off track and a little hard to replicate on a domestic scale but I would imagine the same theory of making the wort and the collant turbulant would still apply.

Regards Derrick

 

[Duff]

Trent,

I made one yesterday for around $40. I used my old immersion chiller and cut 4m off that. If you read the MoreBeer blurb theirs are 12f so is the same length. Then purchased some 20mm OD tubing, fittings, etc., then spent the next hour swearing and cursing trying first to get the tubing on. It wasn't as simple as sliding it around as I thought, so you will have to straighten your tube out as best as possible first (watch for kinking) and have an extra set of hands around (SWMBO) to help. Make sure the each end where you slide the tubing through the elbows are as straight as possible otherwise squaring up compression fittings with olive flanges are a real PITA. It all finally came together and as you are thinking, I am using gravity feed through it regulated by the ball valve on the kettle, while using a small aquariam pump in an esky of ice water to pump against the flow, returning to the esky with simple garden hose and snap on fittings. It made SWMBO very happy as now the only water I'll use now to chill will be the quantity within the esky and while my hands have a few cuts today, I am looking forward to using tomorrow. I'd post some pics but the camera is in for repair, I'll try my phone camera later today if you want. HTH.

Cheers.

 

[shmick]

G'day Trent

I use a 1/2" 15m gravity fed CFWC and the only problem I have is that I have to slow down the flow from kettle to about 1/4 tap open to get the temp down in one pass. A longer one might do better.
Takes about 15-20 mins for a 22l batch to get to about 3degC above tap water temp.

I bought a 25m roll of 20mm black poly pipe from bunnings for about $6 thinking if it was no good I wouldn't be out of pocket much. Works fine - just had to clamp it securely at each end with hose clamps and smear a bit of high temp black silicone around the joint to stop a slow drip under full tap pressure.

I know the poly pipe isn't rated to boil temps but if you turn the cooling water on first and use a non heat conducting transfer hose it isn't a problem. Highest outflow water temp I've ever measured is 65degC.

I coiled it around a fermentor to get the size (400-450mm?) but I'm thinking of coiling it a bit tighter (300mm) so keeping it level (horizontal) isn't as critical. With the larger diameter you have to keep it fairly level or some of the wort gets trapped in the coils and you have to swirl it around bit to get the last out.

From memory it cost about $20 + copper pipe.
2 x Copper Tee pieces (1/2"-1/2"-3/4")
1 x brass click on hose joiner cut in half and silver soldered to the Tees for in & outflow water hose connections.
4 x ss hose clamps (2 for poly pipe, 2 for transfer hose connections)
1 x roll poly pipe
2 hrs labour

Hardest bit was getting the copper pipe thru' the poly but a bit of detergent fixed that.

I've thought about buying a pump to recirculate the wort thru the chiller until cool but I could always just build a second unit and put it in series as Crazy suggested. Space might become an issue though. :chug:

 

[big d]

here you go trent.the innards of a chiller thats convoluted.

View attachment 5699

cheers
big d

 

[Screwtop]

I bought a 25m roll of 20mm black poly pipe from bunnings for about $6 thinking if it was no good I wouldn't be out of pocket much. Works fine - just had to clamp it securely at each end with hose clamps and smear a bit of high temp black silicone around the joint to stop a slow drip under full tap pressure.


From memory it cost about $20 + copper pipe.
2 x Copper Tee pieces (1/2"-1/2"-3/4")
1 x brass click on hose joiner cut in half and silver soldered to the Tees for in & outflow water hose connections.
4 x ss hose clamps (2 for poly pipe, 2 for transfer hose connections)
1 x roll poly pipe
2 hrs labour

Could you post a Pic Shmick?

 

[Ross]

Trent,

I made one yesterday for around $40. I used my old immersion chiller and cut 4m off that. If you read the MoreBeer blurb theirs are 12f so is the same length. Then purchased some 20mm OD tubing, fittings, etc., then spent the next hour swearing and cursing trying first to get the tubing on. It wasn't as simple as sliding it around as I thought, so you will have to straighten your tube out as best as possible first (watch for kinking) and have an extra set of hands around (SWMBO) to help. Make sure the each end where you slide the tubing through the elbows are as straight as possible otherwise squaring up compression fittings with olive flanges are a real PITA. It all finally came together and as you are thinking, I am using gravity feed through it regulated by the ball valve on the kettle, while using a small aquariam pump in an esky of ice water to pump against the flow, returning to the esky with simple garden hose and snap on fittings. It made SWMBO very happy as now the only water I'll use now to chill will be the quantity within the esky and while my hands have a few cuts today, I am looking forward to using tomorrow. I'd post some pics but the camera is in for repair, I'll try my phone camera later today if you want. HTH.

Cheers.

[post="104834"][/post]​

Duff,

Are you just using the esky for the last few degrees, or the whole cooling process?
If using for the whole process, my guess would be that you'll be needing to quickly add a lot of ice to keep the temp down - not sure it would be practical??

cheers Ross

 

[Duff]

Trent,

I made one yesterday for around $40. I used my old immersion chiller and cut 4m off that. If you read the MoreBeer blurb theirs are 12f so is the same length. Then purchased some 20mm OD tubing, fittings, etc., then spent the next hour swearing and cursing trying first to get the tubing on. It wasn't as simple as sliding it around as I thought, so you will have to straighten your tube out as best as possible first (watch for kinking) and have an extra set of hands around (SWMBO) to help. Make sure the each end where you slide the tubing through the elbows are as straight as possible otherwise squaring up compression fittings with olive flanges are a real PITA. It all finally came together and as you are thinking, I am using gravity feed through it regulated by the ball valve on the kettle, while using a small aquariam pump in an esky of ice water to pump against the flow, returning to the esky with simple garden hose and snap on fittings. It made SWMBO very happy as now the only water I'll use now to chill will be the quantity within the esky and while my hands have a few cuts today, I am looking forward to using tomorrow. I'd post some pics but the camera is in for repair, I'll try my phone camera later today if you want. HTH.

Cheers.

[post="104834"][/post]​

Duff,

Are you just using the esky for the last few degrees, or the whole cooling process?
If using for the whole process, my guess would be that you'll be needing to quickly add a lot of ice to keep the temp down - not sure it would be practical??

cheers Ross

[post="104882"][/post]​

The whole lot Ross, I just have 2 or 3 3L frozen milk bottles in there. Goes well when the run off from the kettle is slow. I only have the ball valve cracked maybe a quarter open. Run off into a 20L cube with tap, then drop from a height into the fermenter with grain/hop bag, to catch any hop debris that got through, to aerate. Half full the fermenter, pitch yeast, then top off.

Cheers.

 

[Ross]

The whole lot Ross, I just have 2 or 3 3L frozen milk bottles in there. Goes well when the run off from the kettle is slow. I only have the ball valve cracked maybe a quarter open. Run off into a 20L cube with tap, then drop from a height into the fermenter with grain/hop bag, to catch any hop debris that got through, to aerate. Half full the fermenter, pitch yeast, then top off.

Cheers.

[post="104903"][/post]​

What size esky of water are you using? I'm guessing it must be pretty big for the volume of water you would need for efficient cooling?

cheers Ross

 

[shmick]

I bought a 25m roll of 20mm black poly pipe from bunnings for about $6 thinking if it was no good I wouldn't be out of pocket much. Works fine - just had to clamp it securely at each end with hose clamps and smear a bit of high temp black silicone around the joint to stop a slow drip under full tap pressure.


From memory it cost about $20 + copper pipe.
2 x Copper Tee pieces (1/2"-1/2"-3/4")
1 x brass click on hose joiner cut in half and silver soldered to the Tees for in & outflow water hose connections.
4 x ss hose clamps (2 for poly pipe, 2 for transfer hose connections)
1 x roll poly pipe
2 hrs labour

Could you post a Pic Shmick?

[post="104881"][/post]​

Sorry Screwtop - I don't have any photos - just a few basic CAD drawings

 

[Screwtop]

Thanks Shmick, thats good.

 

[warrenlw63]

Does anyone know if I should crimp the tube if using gravity

[post="104819"][/post]​

Trent

Crimping the tube may also increase the likelihood of developing crevices inside the inner tubing thus giving lodgement areas for unseen nasties to congregate. h34r:

I've head of some intrepid brewers in the US making their own convoluted pipe by winding copper wire around their copper pipe and tacking (soldering) it on.

Would be a tedious job though. Then begins the nightmare of feeding the inner pipe into the outside tubing

Warren -

 

[timmy]

Here's my CFWC I made up from a few spares.

From memory its 8m long, 3/8" tube inside 5/8" then rolled around an lpg bottle. A fittings are silver soldered with 1/2" BSP socket weld nipples on the wort in and wort out.

Brings wort to within 2-4 degrees of the water temp depending on the rate i pump through it.

PS Note the Jaycar thrumometer, gave it a run yesterday and it still works!

 

[Trent]

Thanks to everyone for all the replies
I had some mates swing into town on friday that I havent seen since London 3 years ago, so I choofed off and went surfing for the weekend, that is why I have been absent from the discussion! All the pics, and CAD drawings, have helped alot, and a thanks also to Big D for the pic of the convoluted chiller, I understand how it gets the turbulence now (I thought the convolutions were on the INSIDE of the pipe! :lol: ). Duff, I would love to see pics of your chiller, if ya dont wanna post em up here, then feel free to PM em to me. Schmick, do you think yours doesnt chill all that well because it is TOO long? I read on another thread (that I am about to go back and re-read) I think it was Batz saying that at a certain length the flow stops being turbulent and becomes linear, hence hardly any chilling ability. I will go read it now, and answer my own question, and if it is related to length, I will PM ya.
All the best, and thanks again
Trent
EDIT - Couldnt find the page I had seen, I think now it may have been Sosman putting the link up. I found it in another thread, Doc had put it up, and it appears that longer tubing doesnt hurt, but it says you need a fast flow to get turbulence. The missus needs the phone now, so I have to go, but its at http://brewery.org/brewery/library/ThermoCS0995.html