The Beer Journals

Chilling

The goal is not only to cool your wort, it is to chill it quickly to get the proper clumping of the protiens and debris. This "cold break" material is not harmful, but it is better to leave as much behind in the kettle as possible. Even if you have to dump everything into the fermenter, don't worry, you will rack the beer off this debris later when it finishes fermenting, but you need it to clump now.

There are lots of ways to chill your wort, and the basics are covered in all of the brewing books, so I will not cover them again. As I state frequently, I'm just documenting my method that works for me, and that will be in use if you show up for a brew day.

Because we are in Florida, we never have the benefit of cold water to run through our chillers. So it doesn't matter if you buy that fancy new plate chiller, it won't get the wort any colder than your cooling water, and it won't get cold very quickly if you don't have a good temperature differential. The temperature differential is the difference between the temp of your wort, and the temp of the cooling water, this is critical in any case of using a system that utilizes water for cooling.

The basic tools of the chilling job are immersion chillers (I.C.), counterflow chillers (C.F.), or plate chillers. Plate chillers are the most efficient, counterflow chillers are good, and the immersion chiller is the simplest. None of them work without cold water to run through them.

Immersion Chillers

I used an immersion chiller for a few years because I'm cheap, and it's easy. Now I'm also using a plate chiller for my main system. Because the immersion chiller can be thrown into the brewpot in the last 15 minutes of the boil to be sanitized, and that the wort never goes through the inside of this chiller, the IC has the least chance of contaminating/infecting your beer. (infection is an incorrect term for bacterial growth in beer)

To get the best performance I tried multiple configurations. I first ran tap water through a pre-chiller in an ice bath, and then to the IC in the kettle, and then the water went into the yard to water the grass, but that wasted water and a lot of ice too.

I pumped ice water through a closed system, into the pre-chiller in ice water, to the brewpot chiller, and back through the pre-chiller. This worked, but went through a lot of ice. Too much ice to be practical.

I then read about the differential being the important thing, and started using that to my benefit. Although we don't have cold tap water, we do have a good differential when you consider that the wort is ~212F when chilling starts, and the tap water is ~80F. This allows me to just run the tap water through the IC until I start reaching the point where the temps just don't continue to drop, which is ~100F. Seems like a 20 degree differential is the minimum for efficient cooling. This water runs out into buckets, and is used to fill the washing mashine to wash a load of clothes on brew day. It is also used for cleanup, and for filling my spa, so it is NOT wasted.

Once 100F is reached, I disconnect the garden hose, and connect the output of my submersible pump (that I have placed in a cooler filled with water and ice). Cheap quick-disconnects are used here to make this easy. The pump is started and the output hose of the IC is let run for a second to clear the really hot water before placing it into the cooler with the pump. You are now recirculating your chilling water.

Through the whole process I'm stirring or moving the IC in the brewpot, and when recirculating I also move the ice water around in the cooler. Keeping the liquids moving prevents a boundary layer from forming and makes the process more efficient. Some folks have come up with numerous devices to do this automatically, but I'm happy doing this manually.

For the ice, I make blocks in the freezer using Tuperware-type containers, and I use the icemaker as well. I break up the blocks when they are placed into the cooler. Remember that making ice takes energy too, so this is why we don't just make a ton of ice and use it from the start. Also, most folks don't have the freezer space to store the large amount of ice that would be required if you used ice water recirculation from the start. If you do have the freezer space, that is fine as well, so do what you decide is best. Just keep in mind that the goal is to waste the least amount of resources while still chilling the wort quickly.

For my early IC, I used a 50' coil of 3/8" copper pipe from the plumbing department of the local hardware store. You can use a bender for the tight bends, or a better and easier way is to solder copper fittings to make the turns required. You can also buy these pre-made quite reasonably these days. I just hose clamped some reinforced vinyl hose to the ends of the copper pipe (no fittings) and then added some cheap quick disconnects to the ends of the vinyl hose. Later chillers were made using 1/2" copper and soldering the joint instead of making bends. This worked better and gave less resistance.

I have a quick disconnect rigged for the garden hose, and the same coming from the output of the submersible pump. (both the garden hose and the pump feed the same input of the IC.

The output hose of the IC doesn't need to have a quick disconnect, but must be long enough to reach back to the cooler for recirculation.

Keep this simple folks, and you will be happy!

Plate Chiller

I finally bought a Blichmann Therminator plate chiller for my brewery. I was doing well with my IC, but I had added a pump, and I thought this would be a good addition to the rig for faster and more efficient chilling, with less exposure to the environment. I have set it up to recirculate the wort back to the kettle until the desired temp is reached. With the warm Florida water, I can't do a single pass into the fermenter, and even when using an ice water recirculation pump, the resulting temperature on a first pass is not as controllable as I'd like. Using the recirculation method I can now get the temp to the exact degree before transfer to the fermenter. In addition, my chilling time goes from ~40 minutes for a 10 gallon batch, down to ~10 minutes, and the time depends more on when I switch from tap water to the ice water pump than anything else. I'm also using less ice with the plate chiller due to the efficiency, but that ice disappears fast!

The Big Chill

After trying everything else to battle the hot Florida tap water, I figured I'd go BIG. I took two Blichmann Therminators and conected them in series. The first one after the wort pump uses tap water to bring the wort down to ~80-90F, and the second is fed with ice water using the submersible pump to bring the wort down to pitching temps. I have created a few different variations you can see here but went back to the inline modular setup and added tri-clamp fittings for easy configuration. I know they are not sanitary due to the threads, but neither are the chillers and the whole setup gets heat sanitized each time anyway.

So far the method is to circulate hot wort to sanitize the system, then while circulating the tap water is turned on full, after a few seconds the ice water pump is turned on, a valve is closed briefly to allow a hose to be directed into the fermenter, and then the valve is opened to allow the wort to flow into the fermenter until the kettle is empty. I used to recirculate more, but now we can go direct from boiling kettle to fermenter with this setup and not go through a lot more ice.

In the first real run during Big Brew 09, the wort was below 60 going into the fermenter, and we used about half the ice we normally do. This is awesome, although just about the most expensive way to efficiently chill wort. Unless you brew larger batches, and live in a hot climate, this is probably not your solution.

Here is the entire setup showing the pumps, hoses, chillers, and submersible pump in a bucket. The only things missing are the kettles.

Here is the box of pumps. It is a $1.99 plastic storage box from Target that was thin enough to allow me to take the pump heads off the motors and poke the motor through a hole cut into the box, and reattach the heads. This keeps the spills off the sensitive motor housings when my clumsy butt is brewing. I'm going to improve this setup when I get time. There are holes drilled into the sides of the box to let the motots get cooling air. The notations on the top of the box are simly the colors of the plugs so I know what motor I'm plugging in. I'm going to build a switch box, but until then, this is it.

Below is the newer prototype chiller setup, with pump attached. Eventually this will be on a solid frame. What this allows different than the previous is to be able to use one or both chillers as an option. With the pump attached to this stack it compacts the setup a bit more. This whole design will change as I improve it.

On the lower right you will see the valve attached with a "T" and some disconnects. This is to be able to drain the RIMS tube and any attached hoses without needing to move anything. Just to get the most wort out of the system easily.

Why Not Use Stainless For A Chiller????

Recently, Rick from Michigan on BeerAdvocate.com asked why they should not use stainless for an immersion chiller. The reason is that stainless is very inefficient. Yes, the same stainless we use for our keggles is really bad at transferring heat! This is why the better stainless pots have a multi-layer sandwich bottom. Here are the facts that Rick dug up...

Thermal conductivity is the quantity of heat transmitted through a unit thickness in a direction normal to a surface of unit area, due to a unit temperature gradient under steady state conditions.
Thermal conductivity, or heat transfer coefficients, of some common materials and products can be found in the table below:

Copper 401
Stainless Steel 16
Silver 429
Steel 46
Aluminum 250

All that said, we probably won't see much difference as homebrewers as we tend to build the chillers with enough length to make up for the thermal inefficiency of the stainless.

Here is a friend's IC that he made with soldered fittings. Very simple and strong. All our chillers are now built this way.

Here is my 50' IC. The big bend at the bottom fits over the pickup tube in the keggle. It is not pretty, but I don't really care. This chiller has since gone to the recycling center in favor of a 1/2" model

Here is the 1/2HP submersible pump from Harbor Freight. I'd suggest getting the 3/4HP or 1HP, but this works fine. It is about $30.

You can see the male part of the cheap quick-disconnect on the hose at the bottom.

I've also zip-tied the float switch to the side so the pump stays on when plugged in.

You don't need to use a cooler for the pump and ice, but it helps a bit to make the ice last longer. The cooling process doesn't last really long from 100F down to pitching temp, so any container will work for the pump and ice.

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Email me at Dean_Palmer@jabil.com if you find errors, bullshit, or have questions.