Glycol for Chillers

Glycol FAQ

Everything you need to know about Glycol

Glycol is a very important element in any cooling system. Despite its ubiquity and its importance, most customers don’t fully understand all that it does. In an effort to clear up some of the confusion about glycol, here are our answers to the most commonly asked questions.

What is Glycol?

Glycol is a water-miscible organic compound in the alcohol family. It is commonly used for cooling in industrial and mechanical applications. Glycol is sometimes called antifreeze or a coolant. Though it acts similarly to a refrigerant, and someone may refer to glycol as a refrigerant, this statement is incorrect. Glycol cools solely through heat transfer in an exchanger; whereas, refrigerant uses an evaporation-condensation cycle to remove heat.


What does glycol do in a processing cooling system?

The most important role glycol plays in a process cooling system is to adjust the temperature range of the system. Without any glycol in the system, the water will freeze at the normal 32°F (0°C). In this case, the system ambient temperature can never go below this temperature. However, many systems need temperature flexibility as pipes travel outside and into unheated areas. Adding glycol to the water lowers the freezing point. The percent of glycol determines what the new freezing point will be.

A lower freezing point means process fluid can be kept at colder temperatures. A greater difference between medium temperatures allows for a faster heat transfer process. Heat always travels in the direction of higher temperature to lower temperature. When a coolant with a colder temperature is used, more of the energy can be transferred from the other fluid or process to the coolant.


What are the benefits of using glycol in my system?

Glycol often contains corrosion inhibitors which can help to prolong the life of components. Its main function is to enable a cooling system to operate at temperatures below the freezing point of water. Certain systems may require this lowered cooling for optimum performance.


What percentage of glycol does my system require?

Deciding on the perfect glycol-water mixture is critical to your chiller's operation. You will need to consider factors such as ambient temperature, desired lowered temperature, and heat transfer rate. The best way to determine a percentage for your system is to talk to a Chase Cooling Systems Expert. As there can be adverse effects on the cooling system when using glycol, the glycol concentration should be limited only to what is required for freeze protection.


Are there different types of glycol?

Yes. There are two types of glycol commonly used for process chillers: Propylene and Ethylene Glycol. These products vary on metrics such as performance, environmental factors, and general safety. The specific needs of your process will determine which glycol type is best for your system.


Is glycol safe to use around food and beverage products?

In general, propylene glycol is considered food grade and can be used in food and beverage operations. Most brewery applications use this type of glycol. Additional certifications such as United States Pharmacopeia (USP) stamp can be sought to ensure that any glycol in the mixture indeed is safe for consumers.


Where can I purchase Glycol?

Glycol can be purchased from reputable vendors, including Chase Cooling Systems. When purchasing glycol, know the concentration you need and the concentration you are purchasing. Glycol comes in stock concentrates as well as in set blends. It can be ordered in 55 gal drums, 5 gal pails, or bulk 275 gal totes. Always make sure you are purchasing the appropriate grade glycol. Automotive anti-freeze should never be used in a chiller.


How do I change the ratio of my glycol mixture?

If you have purchased a ratio that is higher than what your system needs, do not panic. You can still use this blend. However, you will need to perform onsite mixing. This process will involve adding water to the blend. Only use filtered, distilled or reverse-osmosis water. General tap water often has minerals such as calcium that can affect the chiller. After mixing and filling the system, any air pockets will need to be removed to prevent system frothing in the chiller.


What type of piping should I use for my glycol mixture?

Copper or ABS piping remain industrial standards for system piping. PVC is also sometimes used. The most important thing to consider when setting up a new system, is that the piping is properly sized. An undersized pipe may accidentally increase the pressure and could risk the rest of the system. Whereas, an oversized pipe may lower overall efficiency. Glycol is not recommended with galvanized piping, as it may adversely react with Zinc.


Will adding glycol change anything in my chiller setup?

Since many chillers are factory set for water only solutions, some minor adjustments may need to be made. Areas such as the evaporator, pump, and hot gas bypass valve may need adjustments. Glycol has a lower specific heat capacity and a lower heat transfer efficiency. These factors must be considering when designing for a particular system. A trained professional should be able to easily make the necessary changes. The addition of glycol also changes maintenance concerns, as the new element will need to be tested and maintained along with the mechanical elements of the machine.


Should I use glycol in my system?

If your system or atmosphere have the potential to go below 32°F (0°C), then a glycol-water mixture should be used. A chiller’s process fluid should never freeze, as this stops the chiller’s ability to do work, and could even cause mechanical damage. To prevent these problems, talk to an expert and discover the best glycol mixture for your system.

Still have questions? Comment below and one of our experts will answer it as soon as they can. Or even better! Call a Chase Cooling Expert.


What are the different types of compressors in industrial chillers?

If you are currently in the industrial chiller market, you have probably noticed that different chiller units have different compressor types. You may be wondering what the details of these different compressors are. Having a basic understanding of the core mechanisms of your unit not only provides you with a better appreciation for the unit, but also helps in your general maintenance and troubleshooting efforts.

Compressors are vitally important to the overall chiller system. They take
in low-pressure refrigerant vapor from the evaporator and compress it. The
resulting hot, high-pressure gas is discharged to the condenser.  Once cooled in the condenser, the refrigerant
continues through the expansion device and enters the evaporator. There, it
chills the process fluid.  Without a
working compressor, the refrigerant cycle simply cannot function.

Chase Chillers feature four different types of positive displacement
compressors: reciprocating, rotary vane, scroll, and screw. The compressor type
largely aligns with the size and capacity of the chiller itself. Continue
reading below for more information on the basics of the different compressor
types.  

Reciprocating
Compressors

Reciprocating compressors use a piston and cylinder to compress incoming refrigerant. As the piston moves downward, refrigerant is drawn into the cylinder. The piston then moves upwards compressing the refrigerant and discharging it downstream to the condenser. Intake and exhaust valves ensure that the refrigerant does not flow backwards.  These types of compressors are very economical and efficient in smaller applications.  As with rotary vane and scroll compressors discussed below, reciprocating compressors consist of a hermetically sealed design. Chillers set up for small to medium heat loads, such as QBS and some QBE models match well with this type of compressor.

Rotary
Vane

Rotary vane compressors typically are quieter than other options. They consist of vanes or blades that are attached to a core rotor. The rotor is positioned off-center within its cylinder, creating multiple areas of varying sizes. The refrigerant enters the cylinder at the largest of these areas. As the rotor turns, the fluid is forced into smaller areas and compresses. Once compressed, the fluid exits the cylinder and continues through the rest of the system. Typically, industrial chillers with this compressor type only contain one compressor per unit. This compressor type is available in certain QBE models and the smallest CWT model.

Scroll

The most common compressor type in industrial chillers is the scroll. It is a powerhouse of a design and is able to handle significantly larger loads than the other compressor types. Found in our larger units, CWB, CWE & CWT, scroll compressors work by compressing the refrigerant between two spiral plates, one stationary and one orbiting. As the spirals move in an offsetting pattern, the trapped air is forced into smaller spaces as it moves towards the center. The compressed fluid exits through the center outlet and into the rest of the system. Multiple scroll compressors can be used in a single cooling unit, a feature great for building in redundancy and providing highly efficiency partial loads. With fewer moving parts, they are often more reliable and efficient than reciprocating options.

Screw

Rotary screw compressors have two interlocking helical rotors mounted inside a casing. As the rotors turn, the gas is forced from the suction end of the casing to the discharge end. The available space between the rotors and the casing becomes increasingly smaller as the gas moves along the length of the screw, increasing the pressure. Screw compressors are useful for varying the cooling output and are found in the largest chiller units. This design is able to limit how much refrigerant is delivered and lends itself well to meeting the variable needs of some cooling processes. Chillers in the CWV series have this compressor type.

The chart below outlines which compressor type is present in which Chase Chillers model:

Reciprocating Rotary Vane Scroll Screw
QBS
QBE
CWT
CWE
CWB
CWV

Regardless of which unit you choose, you can trust that it will be backed by the Chase Cooling Systems quality assurance. Each compressor type has its perks and benefits certain systems over others. To make sure you have the best unit for your system, work with one of our cooling experts. They are available for consultation regardless of where you stand in the buying process. We want you to find the best fit for your needs. Our years of experience and knowledge make us a strong resource for this process.


Chase Chiller Electrical Panel

Caring for Industrial Chillers

Chiller Preventative Maintenance

You value your chiller. It’s important for your system to
work properly. You want it to operate well. To run smoothly. To last a long
time.

You don’t want problems, delays, or shutdowns. So how can you prevent these from happening? By taking good care of your chiller, of course! Just like any machine, industrial chillers require regular, dutiful maintenance. Here is a checklist of 6 simple tasks you can do to keep your chiller in top shape.

  1. Pay attention to alarm signals. Every chiller design is different. However, almost every brand will contain automatic alarms. If something major is wrong, then most chillers are smart enough to recognize it. The built-in alarm system should let you know that there is a problem. In order to fix the problem, of course, you’ll need to know what the alarm codes mean. Consult your user manual for answers.
  2. Check & clean water strainer. The overall cleanliness of your system will determine how often this task needs to be performed. Depending on ambient conditions, complete this task on a weekly to monthly bias. To keep smooth operations, you must prevent grime and filth from entering into the system.
  3. Clean the condenser coils. Condenser filters and coil surfaces will accumulate dirt, which could impact overall chiller performance. Contaminants & debris complicate the heat transfer process and increase the effort required to perform the same amount of work. These substances prevent proper temperature from being achieved and lower what your chiller can do. At the very minimum, cleaning of these elements should occur monthly.
  4. Confirm the pressure of inlet, outlet, and, if applicable, tank. If the working conditions have changed for your chiller, then your chiller will not perform at its best. Regularly checking these metrics allows users to catch issues before they become too expensive. Changes here often signify a larger problem, especially if not corrected. If the pressure continues to be incorrect, you may need to call for engineering assistance.
  5. Maintain proper water level and flow.  Low water level in the tank can cause the pump to cavitate, leading to damage or failure of the impeller.  Non-pressurized tanks should have a sight tube to indicate the minimum and maximum water level.  Pressurized tanks, which must be completely full, usually have an automatic or manual vent valve to expel any air. Check this metric regularly to prevent problems such as the evaporator freezing from low water flow.
  6. Schedule annual maintenance. Since chillers are closed circuit, many users believe there’s no need for service. This belief is wrong. Chillers require the same attention as other mechanical equipment do. To keep in the best condition, you’ll really want to regularly have an expert perform extensive maintenance. Trained technicians are able to test components, such as the electrical and refrigeration, that the typical user cannot.

Completing these basic maintenance tasks on a regular basis should not only increase your chiller performance, but also settle your worrying mind. By taking an active role in your chiller's life, you can take comfort in its increased reliability. With good care comes good quality.


Process Chillers in the Brewing Industry

Why are process chillers so important to the brewing process?

Making the perfect brew requires a lot of preparation and effort. You combine the freshest ingredients, proper techniques, and specialized equipment. But arguably the most important component is the ability to accurately control the temperature throughout the brewing process. Having quality temperature control matters for the quality of the final product. The best way to achieve this control is with an accurate and reliable process chiller.

There are six main steps in the typical brewing process. As the materials
move from raw grains to sugary wort to finished beer, the heat or lack of it
directly impacts the progress made. With each stage comes a new version of the
product, with temperature acting as the driving force.

The heating stages:

The first two stages, mashing and sparging, involve adding hot water to a
mixture of malt. The hot water releases the sugars from the grains. Yeast in
later stages feed on these sugars to transform the liquid (now known as wort)
into beer. The added water needs to be very hot in order to release as much of
the sugars from the malt as possible. If not enough sugar is released, the
yeast will not be able to effectively ferment the liquid in later stages.

Boiling the wort is the third stage. This step is important to kill any
microorganisms and to create a welcoming environment for the hops. The
specifics of the batch will determine the amount and timing of the hops'
addition. Hops, in combination with temperature, act as a key component in
determining final flavor.

The cooling stages

The next stage is when your chiller first makes its appearance. Once the wort has been sufficiently boiled, it will need to be quickly cooled. Not only does the quick cooling prevent the growth of more microorganisms, it also creates the proper temperature to finally add the yeast. If it’s too hot, the yeast will die and prevent the fermentation process from continuing.

Cooling Wort

Usually a chiller pumps coolant through a coiled tube immersed in the hot wort. Wort cooling can also be accomplished in a jacketed vessel or a plate heat exchanger. The coolant, most often a glycol-water mixture, is significantly cooler than the wort. As the coolant moves through the tube, it quickly absorbs the heat from the wort, efficiently cooling the wort to the desired temperature. The exiting coolant, now warmed by heat exchange with the wort, will return in a closed loop to the chiller to be cooled to the necessary temperature once again.

Fermentation

Fermentation is the next stage. Here it is absolutely crucial to reach and maintain the proper temperature. Once the wort has been cooled, the yeast can be added. As the yeast slowly consumes the extracted sugars in the mixture, it produces CO2 gas and ethyl alcohol. Depending on the specifics of the brew, this process can take many weeks. During this time, the mixture must stay at a consistent temperature. If the temperature changes too much, the fermentation process could stop and affect the final flavor.

Yet again, the glycol process chiller becomes important. Fermentation is an exothermic process, meaning it produces heat as it progresses. The longer the wort ferments, the more heat it produces. The brewery chiller removes heat in order to keep the beer taste consistent across batches. Built in temperature controls on Chase Chiller models make this process easier by telling you exactly how the system is performing. The rate of heat transfer is directly proportional to the difference between temperature of the cooled item and the temperature of the coolant. The proper coolant temperature depends on the desired fermentation temperature.

Packaging

Mechanical cooling may also be involved in the final stage of the process: packaging. In order to prevent further fermentation or product change the right temperature is needed. Sometimes the bottling or canning process generates heat that should not be transferred to the finished product. Process chillers can help to maintain the right temperature as the product moves through the packaging line.

Temperature control is crucial in every step of the brewing process. Strong, reliable process chillers, like those from Chase Cooling Systems, bring that support level. So, let a dependable Chase Chiller find the proper cooling balance for consistent products for your system.


Radiator with Cooling Fins

Water-Cooled vs. Air-Cooled Chillers

What’s the Difference Between Water-Cooled and Air-Cooled Chillers?

Two main types of industrial chillers exist: water-cooled and air-cooled. Though both chiller types cool industrial process fluids, how the system rejects the extracted heat differs. The needs of the overall refrigeration system therefore determine the best chiller model. Understanding these various strengths makes choosing a proper system design easier.

Chiller Operation Overview

All industrial chillers have the same basic components: evaporator, compressor, expansion device and condenser. They utilize a closed loop refrigeration circuit to cool a fluid (typically water or a water/glycol mixture). The compressor circulates the refrigerant through the closed loop, from condenser to expansion device to the evaporator and, finally, back to the compressor.  As the refrigerant flows through the circuit, the expansion device, usually a valve or a capillary tube, meters it. The evaporator extracts the heat, lowering the fluid temperature and raising the refrigerant temperature. The closed loop system means that the extracted heat must be expelled elsewhere from the system. This role falls to the condenser.  Refrigerant heated by the evaporator fluid and the compressor, enters the condenser. How the condenser cools the refrigerant determines the key difference between water-cooled and air-cooled chillers.

Differences in the Condenser

Air-cooled chillers have condensers that use ambient air to cool hot refrigerant. They are similar in construction to the radiator on a car or the outdoor portion of a home air conditioner.  Refrigerant flows through a series of tubes mechanically assembled with an array of closely spaced fins.  A fan blows ambient air through the fins and over the outside of the tubes, cooling the refrigerant flowing inside. The excess heat is released to the air and can be recovered for use elsewhere in the facility.

Contrastingly, water-cooled chillers use water to cool the refrigerant in the condenser. Water-cooled condensers are typically tube-in-tube, tube-in-shell, or plate-type heat exchangers in which water from a cooling tower or other water source cools the refrigerant.  The refrigerant and cooling water do not come in direct contact with each other, rather they flow in separate passageways within the heat exchanger which are in close contact for efficient heat transfer. The water flows over the refrigerant tubes and absorbs the excess heat, thus lowering the refrigerant to the necessary temperature for use in the system.

Environmental Installation considerations

Though a great deal of variety exists within both air-cooled and water-cooled chillers, some general installation rules do apply. Knowing the ultimate arrangement of a system can help to guide your chiller choice. For each of the following situations, the most practical chiller type is described.

Indoor areas:

Both air-cooled and water-cooled chillers are installable indoors. However, the chiller type will dictate the room’s arrangement. Indoor air-cooled chillers need ventilation to the outside. Sufficient fresh make-up air allows for the maintenance of a suitable temperature within the space. Water-cooled chillers do not require ventilation or fresh make-up air. They are almost exclusively installed indoors. Since they use water for cooling, the water conducts the heat out of the room, eventually exhausted to ambient, often via a cooling tower.

Outdoor Areas:

Almost all outdoor installations will be air-cooled chillers . In these installations, the heat rejected at the condenser simply dissipates into the ambient air. Outdoor installations require properly configured electrical control panels, based on the expected range of environmental conditions.

High Temperature Environments:

Water-cooled chillers work great in high temperature environments since they do not rely on ambient air for cooling.  Thus, they can be placed in hot mechanical rooms or in spaces with minimal ventilation.

Small Spaces:

The condenser on water-cooled chillers is more compact than an equivalently sized air-cooled unit.  This can result in an overall smaller unit, especially in the case of high capacity chillers. However, the entire refrigeration system will still require sufficient space.

Water-scarce areas:

Use an air-cooled unit. The cooling medium, ambient air, does not require any connections. Nor does a chiller with an air-cooled condenser need a cooling tower. These installations have lower overall environmental concerns surrounding water treatment and removal. An air-cooled chiller should be the best choice for water conservation.

Cost considerations

As with any equipment purchase, price will be a consideration. However, the difference in initial cost between an air-cooled and a water-cooled chiller may be misleading. Instead, it is important to factor in all lifetime costs to create the most accurate comparison.

With indoor installation of an air-cooled chiller, costs associated with duct work, fans, and controls for maintaining proper air temperature in the room may exist. Energy consumption costs may be higher for these chiller models due to its basic operating design.

Often times water-cooled units have a lower initial price. However, they generally have more operational costs, and will typically require the installation of a cooling tower. When using a cooling tower in conjunction with a water-cooled chiller, additional costs may accrue from the regular monitoring of water quality, treatment of the water, and the operation of fans and pumps. However, water-cooled chillers allow the refrigeration system to operate at lower head pressure, making them more efficient and less costly to operate than air-cooled chillers.

Factors such as water costs, efficiency ratings, and electricity can dramatically change the lifetime price of a chiller.

Which one do I choose?

If you are uncertain about how to select the right chiller for your system, our cooling engineering experts are always available to help.  Use these sizing factors to gain quick insight into what your system requires.

If after all these considerations, you still cannot make a decision, focus on cooling capacity. Use the process itself to determine the required cooling amount. This is the number one factor in determining the proper chiller size for your system.

Choosing between water-cooled and air-cooled chillers is not an easy process.  However, with the right support and expertise, working through your system’s individual needs will lead to the best equipment purchase for YOU.

Be sure to explore the main chiller options available from Chase Cooling Systems.


Fabtech Tradeshow Main View

FABTECH 2018: Bringing Reliable Process Cooling to the Metalworking Industry

Bringing Reliable Process Cooling to the Metalworking Industry

We are proud to announce that Chase Cooling Systems will be exhibiting at FABTECH 2018. FABTECH is North America’s largest metal forming, fabricating, welding and finishing event. The annual conference cosponsored by The Fabricators and Manufacturers Association, SME, The American Welding Society, Precision Metalforming Association, and Chemical Coaters Association International will be held November 6-8 at the Georgia World Congress Center in Atlanta, GA.

FABTECH connects sellers and buyers in a centralized location to discuss products, industry changes, and more. With a mixture of product specific exhibitors, educational sessions, and inspiring lectures, FABTECH is projected to draw 30,000 people in the manufacturing sphere. Representatives from Chase Cooling Systems will be located in Booth B8673 to discuss process cooling specifications, applications, and products.

Chase Chiller models from the QBE and QBS series will be on display in Booth B8673 for viewing. With their small size, portability, and power, these chiller series are particularly applicable to the metalworking industry.

The QBE series of air-cooled chillers from Chase Cooling Systems comes fully packaged with refrigeration system, controls, storage tank, and pump. The machines are simple to set-up and integrate well into both OEM equipment and with existing machinery. Cooling capacity ranges from 0.5 to 7 tons, and models include non-ferrous fluid circuits. The customization possibilities of QBE chillers meet a diverse range of applications from resistance welding to lasers to EDM.

The QBS series of portable industrial chillers has up to 0.5 ton of cooling capacity. It is especially suitable for welders. With both 115/1/60 and 230/1/60 versions available, and a small size of 18.4” W X 20.2” D X 24” H, moving the unit from process to process is easy. Optional wheels exist for additional portability. Like the QBE series, all models come fully packaged and include a non-ferrous fluid circuit, an insulated 4-gallon tank, and an integral pump.

In addition to the QBE and QBS chiller models, Booth B8673 will have a dry cooler unit on display. ACW dry coolers use ambient air to cool small, point-of-use applications.

Anyone interested in attending FABTECH 2018 can do so for free by using the promo code 16029733 or by registering at this customized link. We hope to see you there!

More information about FABTECH 2018 can be found at their website: https://www.fabtechexpo.com/

To follow Chase Cooling Systems’ adventures at FABTECH and beyond, be sure to visit our Facebook and Twitter pages.