Things You Should Know About Glycol Chillers & Glycol Cooling System
Posted by Ron on 7th Feb 2023
You often hear about glycol in the context of draft beer. But what is glycol used for? Being one of the main components of a long-draw draft beer system, propylene glycol is used in chillers to help cool the product down and maintain the right temperature as it is being dispensed.
Here in this article, we take a closer look at propylene glycol and why it’s important for draft beer systems and breweries.
What Is a Glycol Chiller
In short, a glycol chiller is a compact refrigeration unit designed to cool down beer and maintain the required temperature as the beer travels through a beer line from a walk-in cooler to the draft beer tower.
Glycol chillers are one of the main components of a long-draw draft beer dispensing system.
What Does Glycol Do in a Chiller?
So, what is glycol? As a substance by itself, glycol is basically an antifreeze. It’s important to distinguish between ethylene glycol (what they use in cars) and propylene glycol, which is used in the food industry since it’s completely non-toxic. That’s the reason why glycol is used in a chiller.
The pure propylene glycol freezing point is -59°C (-74,2 °F), which makes it an ideal cooling agent. You can change this temperature by mixing glycol with water. For most applications, the ideal propylene glycol to water ratio would be 35% – 40%.
Inside a glycol chiller, glycol is used as a cooling agent to ensure that the beer is continuously refrigerated and doesn’t get warm as it travels from a keg in the walk-in cooler to the draft beer tower through a beer line.
How Does a Glycol Chiller Work?
If we look at a typical draft beer system, the glycol chiller acts as a refrigeration unit in it. So, how does a glycol beer system work? Inside the glycol chiller is a reservoir of glycol that gets pumped through the glycol line (or lines) that are placed together with the beer line snugly inside a trunkline.
Due to the fact that the beer lines come in contact with the cold glycol lines all the way from the keg to the draft beer tower, the beer never gets warm and arrives foam-free at the point where it’s dispensed.
Why Use a Glycol System for Beer?
When people ask “why use glycol for beer cooling”, it’s because they are probably trying to make a choice between a kegerator and a glycol chiller. Here are some arguments in favour of a glycol system for beer.
What Are the Benefits of Using Glycol in Chillers?
- Allows you to deliver beer over long distances (up to 450 ft)
- You can serve a bigger number of beer towers with different designs
- Minimizes your pour cost
Suppose you are choosing between using glycol and some other cooling agent for your system. In that case, we definitely suggest going with glycol since it helps to improve the chiller efficiency, extends its service life, and also reduces the vibration and noise levels.
How Much Beer Do You Save With a Glycol System?
As we’ve mentioned before, using a glycol-cooled draft beer system allows you to eliminate foam when you dispense beer at the draft tower, which results in up to 10% of beer that’s not being wasted.
Are There Any Drawbacks to Using Glycol in Chillers?
Generally, there aren’t any. There are just a few things you have to be aware of when you’re deciding on whether to use glycol or not.
- You must maintain the proper temperature range and glycol/water ratio, otherwise the glycol in your system might freeze
- Glycol can be flammable, so use must follow all the safety precautions from the manufacturer/seller
- Glycol is slightly more expensive than the other cooling agents
How to Use a Glycol System for Draft Beer?
The way glycol is used in a draft beer system is very similar to how you would use antifreeze for your car. You just pour the required quantity into a special reservoir and leave it there. The only thing that’s different is that you have to determine how much glycol there should be in a chilled water system (see above).
How to Add Glycol to a Chiller
Every glycol chiller has a reservoir (or, rather, bath) with a copper coil. You have to fill that with glycol mixed with water in the amount specified in the glycol chiller manual (remember, the ideal percentage of propylene glycol is around 35%).
How to Determine Needed Glycol Cooling System for Brewery
The “what size glycol chiller do I need for brewing beer” topic we address in great detail in our separate article (check it out here). In short, you have to consider the following:
- How often do you brew?
- How much time is there between brews?
- Are you going at a steady pace?
Depending on your answers, you will have to come up with the desired tank volume (how many barrels you are able to produce), temperature differential (the difference between the starting temperature prior to cooling and the ending temperature after cooling), and cooldown time (how much time it takes to achieve the desired beer chiller temperature, measured in hours).
Using these numbers and a special table, you can determine the right amount of glycol for your system.
Glycol Piping for Brewery
Glycol piping lines are typically located inside a trunkline, which also hosts several beer lines, all put together and covered with external insulation. Here are some good examples of glycol piping products.
What Types of Glycol Should I Use for Breweries?
You should use inhibited USP-grade propylene glycol, which is deemed safe by the FDA.
Where to Buy Glycol for Chillers
Beverage Craft is the best place to buy various draft beer system parts, equipment and accessories, including glycol. We offer propylene glycol for both compact chillers in 1-gallon cans and for brewery-grade applications, coming in 53-gallon drums.