Unless your first home brewing kit came with a wort chiller, you probably initially used an ice bath to cool down your kettle just as I did when I started. As you’re becoming a more experienced brewer, you understand that you need to efficiently chill your wort. In this post we’ll discuss how to use a wort chiller the right way, what elements impact its performance, what is the best type of equipment and configuration for you. Mastering the cooling process will make a huge difference in the quality of your finished beer, and make your brew day more enjoyable too.
Why bringing your wort to the appropriate temperature timely is essential
There are essentially 3 reasons why you want to chill your wort quickly from 140F degrees to 80F. At 140F and below your wort is exposed to bacterial risks. 80F or lower, depending on the yeast you are fermenting with is a safe pitch temperature. Always know your yeast and refer to the supplier’s instructions.
1. Preventing infection – there is a risk of contamination with wild yeast and bacteria below 140F.
2. Preventing oxidation – wort shouldn’t be oxidized while it’s hot, since at higher temperatures oxygen molecules will bind with certain wort compound until they are freed later in the beer at lower temperatures, creating off-flavors such as stale, cardboard, and sherry-like.
3. Preventing loss of hops aromas – hop oils are volatile and delicate, and will evaporate when not stabilized at a lower temperature quickly. This is why the same hop will have a bittering effect when added early on to the boil and will have an aromatic effect when added late, particularly at flame out or when dry hopping.
4. Preventing DMS – Dimethylsufide is produced in hot wort from S-MM (S-Methylmethionine) mainly present in malted barley kilned at a lower temperature. DMS is a form of volatile sulfur oil compound characterized by its cooked corn or vegetable. It evaporates during the boil and for that reason you should keep not leave the lid on your kettle to prevent it from condensing and from collecting back in the wort. Cover your kettle when the wort reaches 140F. Cooling the wort quickly will stop the production of DMS. Bacterial infection often because of poor sanitation will also produce DMS of a different kind, tasting more stale or rancid.
What you need to know about wort chillers
The cooling performance is function of several factors and is difficult to formulate simply and calculate in theory. You should take these 5 main elements into consideration when choosing your wort chiller, knowing that you will have to experiment a bit to understand how to maximize the efficiency of your equipment and get the most out of your investment. With practice, you will get to know how to use a wort chiller.
- temperature of your water source
- flow rate(s) of the liquid(s) running through the chiller
- surface of heat exchange, and type of metal (copper, stainless steel)
- hose length connecting the chiller to your water source
- agitation of the wort in contact with the chiller (immersion method)
The 3 types of wort chillers and how to use them
Three types of wort chillers are available to the home brewer, each gear’s benefits and disadvantages are described in the next section below, let’s understand first how the different coolers work and their characteristics.
The IMMERSION CHILLER is a very popular system and perhaps preferred by the greatest number of homebrewers. It is a simple coil of copper tubing in which cold water runs and that rests at the bottom of the kettle. It is commonly hooked to your garden water faucet if you brew outside or in your garage, or to any tap in your house. To connect the female garden hose fitting that normally comes with the chiller to your tap you may have to get a male garden hose adapter. You will need to stir your wort to maximize this type of chiller’s results. It is a plus when you want to create a whirlpool, to rack a clearer wort.
When choosing an Immersion wort chiller, look at the type of connections between the copper tubing and the vinyl tubing both for the inlet and outlet. Threaded fittings are best as they won’t lose their shape and won’t leak as easily. Note the OD of the copper tubing and its length, they determine the surface of heat exchange. A 50′ x 1/2″OD chiller features a greater heat exchange surface than a 25′ x 3/8″OD chiller. Some immersion chillers are made with stainless steel, easier to keep clean, but less effective for heat exchange. Some models include a recirculating arm to create a whirlpool with a brew pump.
The COUNTER FLOW (CF) CHILLER is used by commercial brewers as it is particularly efficient in cooling large amounts of wort using less water. The wort is moved outside of the kettle through a copper coil and cold water is run in the opposite direction through an outer tubing, wrapped around the inner copper coil. In this system the traveling wort is in constant contact with the coldest water. This requires a brew pump to transfer your hot wort and a kettle with a spigot. It will chill your wort to yeast pitching temperature in one single-pass. The temperature of the wort coming out can be regulated by adjusting the flow through the ball valve.
A CF chiller is a good tool for brewing lager, and bigger batches, but works with all sizes. Before you decide to invest in this type of chiller, you need a kettle with a valve. Also, think if you are ready to purchase a brew pump as well, and they are not cheap. Lastly make sure you get some silicone, heat-proof tubing to move your hot wort.
The PLATE CHILLER is another type of wort cooling system set up outside of the kettle. It is built very much the same as a car radiator. The cold water passes through small plates in direct contact with identical plates through which the hot wort passes through in the opposite direction to create the same counter effect as in a CF chiller. Because water and wort plates are stacked in an alternating pattern as to maximize the heat exchange surface. This system is the most efficient chiller if you only take the chill down capability.
The pros and cons of the Immersion chiller
- SIMPLE to set up – you won’t need to move your heavy full kettle.
- Only ONE INLET (for the cold water from your source) and one outlet (for the hot water).
- EASY TO CLEAN AND SANITIZE – the outer surface of the tubing only is in contact with the wort and it is easy to clean. A simple way to sanitize it is to immerse it in the wort 10 minutes or so before the end of the boil.
- NO HOT WORT PUMP (brew pump) is needed – because of this reason, it can be an economical piece of equipment compared to a plate or counter-flow chiller. A hot wort pump is $80 and up. Hot wort needs to be racked by gravity or pumped to avoid oxidation at that point. If you use a simple brew kettle with no integrated spigot, you will find that an immersion chiller is a good solution for you when siphoning is the only option to rack your chilled wort to the fermenter.
- EASY TO MAKE YOURSELF – for the handy brewers, building your own immersion chiller is a fairly easy DIY project to do if you’d like to save yourself a few bucks.
- SIMPLE TEMPERATURE CONTROL – this type of cooler allows you to control the temperature of the wort and bring it to the desired mark before racking to your fermenter.
- WORKS WELL WITH MANUAL WHIRLPOOLING – Whirlpooling will actually shorten the chilling time. Some immersion chillers are even equipped with a recirculating arm that automatically generate a whirlpool while increasing the chilling effect.
- AFFORDABLE – Basic models can be fairly inexpensive.
- SLOWER COOLING – the basic immersion chiller takes a bit longer to do the job. As discussed previously, a bigger OD, a longer/ taller coil, combined with cold source water with a high flow rate will increase the performance.
- WATER USAGE – It takes lots of water to run through an immersion chiller. If you consider it takes about 20 minutes to bring 5 gallons from 212F to 72F and your average garden hose flow rate is 6 gallons per minute, it will cost you 120 gallons of water! Of course, in reality, it’s closer to between 60 to 80 gallons because agitating the wort will increase the process efficiency and the colder your water, the less will be needed. Using your kitchen tap will cost you
Note that some home brewers use an ice bath and a pump to lower their water temperature. This is also a great way to recirculate and save large amounts of water.
The pros and cons of the counter-flow chiller
- EFFICIENCY – a very effective heat exchange system. Because it chills faster, it produces a cold break and will reduce chill haze in your beer. It will get you to a lower yeast pitching temperature easily.
- SPEED – depending on the parameters, it could cut down your cooling process by half of the time needed when using an immersion chiller.
- REDUCED AMOUNT OF WATER USAGE – up to 50%, depending on the parameters.
- SINGLE-PASS – when you know how to use a CF chiller, it makes it enjoyable to use. Killing two birds with one stone, chilling and racking directly into your fermenter.
- HARDER TO SANITIZE – “you don’t see what’s inside the wort tubing”. A solution would be to run hot wort through the chiller and recirculate it into the kettle.
- MORE COMPLICATED TO SET UP – you need to connect the chiller to a water inlet, a water outlet, a wort inlet, and a wort outlet.
- BREW PUMP REQUIRED – it is strongly recommended to purchase a pump for a hot liquid to work with a CF chiller. This can be a significant additional expense.
- KETTLE WITH A BALL VALVE – if you don’t have one of those, you might want to add a spigot to your kettle. A DIY project if you’re handy. Warning: be aware stainless steel is hard to drill, and you ideally need a step drill bit.
The pros and cons of the plate chiller
- BEST PERFORMANCE – Just pump the wort through it. It is an inline setup.
- FASTEST CHILLER – it is the system with the best heat exchange surface. Even faster than a CF chiller. It will for sure save you time.
- VERY COMPACT – the bigger Plate chillers are 12″ x 3″ x 3″, and ultra compact units are 7.5″ x 3″ x 4″
- REDUCED AMOUNT OF WATER USAGE – by 50% or more, depending on your source water temperature.
- Single-pass – It makes it enjoyable to use. Killing two birds with one stone, chilling and racking directly into your fermenter
- You need a HOP SPIDER to prevent hop to end up clogging your chiller
- DIFFICULT TO CLEAN AND SANITIZE – the plates are so close to each other that it needs to be disassembled to be cleaned.
- HARDER TEMPERATURE CONTROL – Is it chilling too fast? Some users report they have to wait for the wort to warm up. The way to control the temperature is to adjust the water flow rate.
- MORE COMPLICATED TO SET – you need the same four connections as far a CF chiller
- KETTLE WITH BALL VALVE – this will make your life easier.
- BREW PUMP – it will greatly improve efficiency and ease of use.
A great tip to chill faster and save water
Instead of connecting to your wort chiller to the garden faucet or the kitchen tap, use a RECIRCULATING SYSTEM. It is simple and affordable.
To chill 5 gallons of wort – Use a TUB FILLED FILLED WITH ICE (20 Lb or more depending on your target temperature) with a SUBMERSIBLE WATER PUMP (500 Gallons minimum per minute recommended), feeding your immersion chiller. In less than 20 minutes you will reach 80F degrees using about 5 to 7 Gallons of water in all. The trick is to drain the initial 2 to 3 gallons coming out of the chiller as the water will be hot. When it’s warm (around 110-100F degrees), place the water outlet tube into the ice tub to recirculate.
No matter what type of cooling system you opt for, learning how to use a wort chiller will give you the skills to greatly improve the quality of your beer, as well as make your brewing experience more enjoyable. Any of the 3 types of chillers we reviewed will get the job done. The best system for you will depend on your batch size, your lowest target pitching temperature, your existing set up (is your kettle equipped with a valve?), your budget (are you willing to invest in a brew pump?).
I will leave you with these tips to consider:
- Recirculate ice water in your chiller using a water pump and a tub or a cooler to maximize efficiency and save water
- Agitation without of the wort is key. If you are not using a brew pump recirculating your wort, stir it manually. Make sure you don’t oxidize hot wort.
- Never put a lid on hot wort to keep it DMS-free. Cover it below 140F degrees.
- Be creative with your equipment to maximize heat exchange, reduce water usage and save time. Some brewers use a second chiller in an ice bath to pre-cool their water
I recommend you use a water pump to recirculate your cold water into the chiller. This method will save you 50% of your time and dozens of gallons of water.
How are you chilling your wort, with what type of system? Please share your comments below.
Cheers and to our healths!