What is glycol? If you are in charge of managing a cooling or water system, you may have heard of glycol as one possible component. Glycol is used in some water systems to keep the temperature low and consistent. However, if you are considering taking advantage of the benefits of a glycol cooling system to reduce temperatures or prevent freezing, it is important that you understand what types of glycol exist so that you can make a safe and informed decision.
Definition of Glycol
Glycol is an organic compound belonging to the alcohol family. It is more commonly referred to as antifreeze, and it is known to have a sweet taste. However, it can be toxic and is generally fluorescent dyed or clear and slightly oily in terms of consistency.
The Two Types of Glycol
Glycol is an overarching term that encompasses a number of separate chemical formulae. This is why understanding the type of glycol that you may need and how it will be used is important; some options are toxic, and others are much safer.
Ethylene glycol and its derivatives are more toxic and should be used with care. It is most commonly used as antifreeze in automobiles, brake fluid, HVAC Systems, and some human-made fibers. It is derived from ethylene oxide, which comes from ethylene.
Propylene glycol is the non-toxic variant of glycol. It is similar to ethylene glycol in its physical properties but is used frequently in foods, oral hygiene products, cosmetics, and HVAC Systems. It helps to preserve materials and retain moisture.
In addition to its uses mentioned previously, glycol serves a number of purposes in cooling systems and water systems. One important factor to note is that it is important never to mix different types or brands of glycol in your systems, no matter what function you are hoping to achieve; this can cause it to congeal, clog your equipment and leave freeze temperatures virtually unknown.
Glycol Cooling Systems
In cooling systems, the primary purpose of glycol is to help the system stay as consistently cold as possible without freezing. When glycol is mixed with water, the freezing point of the water drops as low as -60 degrees Fahrenheit. This means that a system that needs to keep large areas cool, such as at an ice rink, can remain frigid and even below the freezing point of water without freezing itself.
In order to calculate how much water to glycol is needed for the solution that is used in the chilling system, you will need to calculate what temperature the system will need to achieve. This temperature is typically just the saturated suction temperature in the evaporator, which tends to be approximately 10°F below the chiller set point temperature. Normal HVAC system temperature call for 35-45% solutions with protection between -10*F to + 10*F.
Used in Closed-Loop Water Systems
In closed-loop water systems, glycol can serve an additional purpose besides simply regulating water temperature. As its more common name “antifreeze” suggests, glycol can prevent the water in a closed-loop water system from freezing. This protects pipes from bursting or cracking as ice crystals form and keeps systems safe from exposure to freezing temperatures. Ethylene glycol is the standard in the industry for freeze protection, but it is not always the right choice. Because it can be toxic, using ethylene glycol in systems where food or drinking water is nearby may be a risk.
Also discharge into surface or sanitary water systems could be an environmental issue. In these instances, such as food service, propylene glycol is more common. However, the freezing point of propylene glycol is not quite as low as that of ethylene glycol, so understanding which option is right for you will require a close examination of your system and your situation by an expert.
Contact the Cooling Tower Water Experts at Tower Water
If you are considering how either ethylene or propylene glycol may be able to improve the function of your water system or cooling system, you may feel confused about how to determine which option is right for you. Determining the proper ratio of glycol to water, which type of glycol to use, and how often it should be replaced is not something you can typically figure out on your own. This is why working with a skilled expert in water systems is critical.
The water treatment technicians at Tower Water set the standard in treatment options such as glycol and would be happy to assist you in examining your unique situation and creating a plan. Glycol offers additional benefits such as corrosion protection, and some types can also help you combat algae and bacterial growth. To understand which type of glycol is best for your system and how to set it up for long-term efficiency, call us at (212) 518-6475 or reach out to the experts at Tower Water to schedule a consultation. Glycol can protect and enhance your system for years to come, but you must be sure to set it up correctly when you start.