Hawaiibboy
Well-Known Member
While purchasing much of your equipment is one of the ways to go when building your home brewery, building parts of it can be rewarding.
One thing you can design and build for your brewery is an immersion wort chiller, which is an invaluable tool to help you cool the wort to yeast pitching temperatures. Besides being fun, it can also save you some money for other supplies or more ingredients. This tutorial won’t tell you how to build the wort chiller but how to design it and to help influence your build. For detailed directions to build your immersion wort chiller go here: https://www.homebrewtalk.com/entries/diy-cost-effective-immersion-wort-chiller.html
So grab a scrap piece of paper, a calculator and a pen and lets get to work:
Step 1: Analysis of Your Boil Kettle and Batch Size
To begin, determine the heigth (H) and diameter (D) of your boil kettle. Many times this is supplied by the manufacturer or the retailer.
If you use a false bottom or screen on the bottom of your kettle determine the height from the bottom of your kettle it sits.
ex: My Polar Ware Economy S/S 10.5gal kettle is 14"Hx15.75"D. I don't use a false bottom, so this is 0".
Batch Size: How much wort will you be transferring to fermentation from your kettle? Some people do partial boils and add water post boil while others may do full volume boils.
ex: I do BIAB at 3-6gal full volume boils. A range is okay to have, just use the larger volume for the design.
Step 2: Determine how high up in your kettle your batch volume will be.
There are a few ways to do this, next time you brew place a SANITIZED s/s ruler to the bottom of your kettle and take a measurement, use a volume measuring stick…
or math:
Using the formula for volume of a cylinder: V= H*𝛑(D/2)2 and the fact that 1US gallon = 231 in3 we can determine the height of the volume of wort in a kettle.
(V*231)/ 𝛑(D/2)2=h where V= your batch size in US gal; D=the diameter of your kettle (from step 1); and h=the height of your volume of wort in the kettle.
ex: (6*231)/𝛑(15.75/2)2=h → 1386/𝛑(7.875)2=h → 1386/𝛑(62.015625)=h → 1386/194.8278319077795=h → 7.113973329313926=h
for our purposes we’ll round that to: 7”=h
Step 3: Designing the Coils
There are now three main things to consider here: the width of the coils (aka how big around the chiller will be); the diameter of the piping to be used for the chiller; how much piping is actually needed.
The width of the coils is completely up to you. I have seen immersion chillers that just barely scrape the sides of the kettle, and I have seen chillers that are less than half the diameter of the kettle. You may be limited in forms that you can use to shape your coils, so this could be a determining factor. Anything that is half the diameter of your kettle to about ¾ the diameter of the kettle should work out well though. The most common form I have seen used is a paint can. For our example we will use the width of my form: another kettle, that is 7” in diameter, as our width of coils (w); w=7”
The diameter of piping is also up to you, but the two most common width’s of copper tubing used are 3/8” and 1/2”. I’ll be using 3/8”, so this will be our diameter (d). This will let us know how many coils we will need to reach our desired height. For the example it is: 7”/(3/8&rdquo
or 18.66666667 coils, or about 18 coils. c=18 I like to round down to the nearest whole number here since I want to keep my tightly bundled coils beneath the surface of the wort.
The length of tubing/piping used is determined mathematically by using the formula for circumference multiplied by the number of coils + the length of the two outlets of the chiller (your kettle height and the distance between the top of the wort and the top of the kettle) plus a little more for the bends and exiting the kettle itself; 𝛑wc+H+(H-h) + 6”.
So in my example:
(𝛑*7*18)+14+(14-7)+6=422.84 inches. So about 35 feet will get the job done!
We have all the info we need now to properly design an immersion chiller that will be completely submerged in your wort, with the most surface area possible given a certain diameter tubing and coil size, while still having the leads of the chiller taller than your kettle, all while using the smallest amount of piping needed.
This works if you don’t allow the coils of your wort chiller to deform and separate from each other. To account for this you can add the seaparation distance into the width of your tubing diameter and recalculate. Personally I want an extra quarter inch between coils to really maximize the surface area of my chiller in the wort. Lets see what happens when we recalculate. The only thing changing is the number of coils: c=11
(𝛑*7*11)+14+(14-7)+6= 268.9 inches or about 22 feet of tubing.
I hope this helps people out there determine the amount of copper to buy if they want to go this far when they DIY their immersion chiller!
Brew on, and brew hard!
One thing you can design and build for your brewery is an immersion wort chiller, which is an invaluable tool to help you cool the wort to yeast pitching temperatures. Besides being fun, it can also save you some money for other supplies or more ingredients. This tutorial won’t tell you how to build the wort chiller but how to design it and to help influence your build. For detailed directions to build your immersion wort chiller go here: https://www.homebrewtalk.com/entries/diy-cost-effective-immersion-wort-chiller.html
So grab a scrap piece of paper, a calculator and a pen and lets get to work:
Step 1: Analysis of Your Boil Kettle and Batch Size
To begin, determine the heigth (H) and diameter (D) of your boil kettle. Many times this is supplied by the manufacturer or the retailer.
If you use a false bottom or screen on the bottom of your kettle determine the height from the bottom of your kettle it sits.
ex: My Polar Ware Economy S/S 10.5gal kettle is 14"Hx15.75"D. I don't use a false bottom, so this is 0".
Batch Size: How much wort will you be transferring to fermentation from your kettle? Some people do partial boils and add water post boil while others may do full volume boils.
ex: I do BIAB at 3-6gal full volume boils. A range is okay to have, just use the larger volume for the design.
Step 2: Determine how high up in your kettle your batch volume will be.
There are a few ways to do this, next time you brew place a SANITIZED s/s ruler to the bottom of your kettle and take a measurement, use a volume measuring stick…
or math:
Using the formula for volume of a cylinder: V= H*𝛑(D/2)2 and the fact that 1US gallon = 231 in3 we can determine the height of the volume of wort in a kettle.
(V*231)/ 𝛑(D/2)2=h where V= your batch size in US gal; D=the diameter of your kettle (from step 1); and h=the height of your volume of wort in the kettle.
ex: (6*231)/𝛑(15.75/2)2=h → 1386/𝛑(7.875)2=h → 1386/𝛑(62.015625)=h → 1386/194.8278319077795=h → 7.113973329313926=h
for our purposes we’ll round that to: 7”=h
Step 3: Designing the Coils
There are now three main things to consider here: the width of the coils (aka how big around the chiller will be); the diameter of the piping to be used for the chiller; how much piping is actually needed.
The width of the coils is completely up to you. I have seen immersion chillers that just barely scrape the sides of the kettle, and I have seen chillers that are less than half the diameter of the kettle. You may be limited in forms that you can use to shape your coils, so this could be a determining factor. Anything that is half the diameter of your kettle to about ¾ the diameter of the kettle should work out well though. The most common form I have seen used is a paint can. For our example we will use the width of my form: another kettle, that is 7” in diameter, as our width of coils (w); w=7”
The diameter of piping is also up to you, but the two most common width’s of copper tubing used are 3/8” and 1/2”. I’ll be using 3/8”, so this will be our diameter (d). This will let us know how many coils we will need to reach our desired height. For the example it is: 7”/(3/8&rdquo
or 18.66666667 coils, or about 18 coils. c=18 I like to round down to the nearest whole number here since I want to keep my tightly bundled coils beneath the surface of the wort.The length of tubing/piping used is determined mathematically by using the formula for circumference multiplied by the number of coils + the length of the two outlets of the chiller (your kettle height and the distance between the top of the wort and the top of the kettle) plus a little more for the bends and exiting the kettle itself; 𝛑wc+H+(H-h) + 6”.
So in my example:
(𝛑*7*18)+14+(14-7)+6=422.84 inches. So about 35 feet will get the job done!
We have all the info we need now to properly design an immersion chiller that will be completely submerged in your wort, with the most surface area possible given a certain diameter tubing and coil size, while still having the leads of the chiller taller than your kettle, all while using the smallest amount of piping needed.
This works if you don’t allow the coils of your wort chiller to deform and separate from each other. To account for this you can add the seaparation distance into the width of your tubing diameter and recalculate. Personally I want an extra quarter inch between coils to really maximize the surface area of my chiller in the wort. Lets see what happens when we recalculate. The only thing changing is the number of coils: c=11
(𝛑*7*11)+14+(14-7)+6= 268.9 inches or about 22 feet of tubing.
I hope this helps people out there determine the amount of copper to buy if they want to go this far when they DIY their immersion chiller!
Brew on, and brew hard!
:smack:
