Brooke Loeffler

Air cooled chillers use the refrigeration cycle to produce chilled fluid, typically water or a mix of water and glycol. This chilled fluid is then capable of removing heat from machinery, food, or other equipment and continuously run back through the chiller.

Air Cooled vs. Water Cooled Chillers

Air cooled and water cooled chillers have many things in common. They both belong to the same vapor compression chilling family, and they both use an electronically driven mechanical compressor to force refrigerant around the system. In fact the majority of their components are the same. The main difference between the 2 is how unwanted heat is ejected from the system.  Water cooled chillers pump water through a sealed condenser and disperse it through a cooling tower. Air cooled chillers use fans to force cool air across the condenser.

A water cooled chiller’s cooling tower and pump take up more space than the fans in an air cooled chiller. Because of this main component difference, air cooled chillers have a more compact footprint. Cooling towers are also more expensive to maintain, making air cooled chillers the clear lower maintenance option. In general, air cooled chillers have significantly lower upfront costs as well.

Components of Air Cooled Chillers

Compressor

The compressor provides the driving force for moving the refrigerant around the system.  There are four main types of compressors. Three of them (screw, scroll, and reciprocating) use positive displacement to create pressure, and the fourth (centrifugal) creates pressure with centrifugal force.

Condenser

The condenser is a configuration of horizontal pipes through which hot refrigerant runs. Air is moved across the condenser to dissipate unwanted heat.

Condenser Fans

These fans represent the main difference between air cooled and water cooled chillers. As they move air across the condenser, unwanted heat is removed from the system so the cycle can start all over again.

Expansion Valve

The expansion valve expands the refrigerant from liquid form to gaseous form before it enters the evaporator.

Evaporator/Heat Exchanger

In the evaporator, chilled water is created when unwanted heat is drawn into the refrigerant before it is fed into the condenser.

Filter Drier

The filter drier protects your chiller by removing unwanted contaminants and moisture from the system. They do get clogged with repeated use and need to be replaced regularly.

Air Cooled Chilling From North Slope Chillers

Air cooled chillers house all of these components in a single space saving cabinet that is easily incorporated into any operation. Air cooled chillers from North Slope Chillers are portable and easy to use no matter the application. Our chillers excel at cooling lasers, welders, food storage containers, lab equipment, printers, EDM, hydroponic reservoirs, plastic injection molds, fermentation tanks, server rooms, oil extraction equipment…the list goes on and on! Contact North Slope Chillers to find the right air cooled chiller for your needs at (866) 826-2993 or [email protected].

Centrifugal chillers are typically the most economical chiller to use for cooling sizable buildings. They can efficiently produce a high flow rate and are ideal for larger applications. Centrifugal chillers usually have fewer moving parts than other varieties, and with less mechanical friction are more cost effective to maintain. Some cooling applications require greater portability and lower cooling temperatures than centrifugal compressors are built to produce. Their range of usefulness is limited by their large footprint and emphasis on volume instead of cooling power.

Types of Compressors

Positive Displacement Compressors

There are 4 main types of compressors found in vapor compression chillers: scroll, screw, reciprocating, and centrifugal.  Scroll, screw, and reciprocating compressors work through the process of positive displacement. Positive displacement compressors capture gases into a chamber, then reduce the volume of the chamber to cause compression.

Centrifugal (Kinetic) Compressors

These compressors use centrifugal force to turn kinetic energy into pressure. As gases enters the compressor, they are spun radially outward causing them to compress. Centrifugal force then throws the gases back out at a high velocity.

Centrifugal Force

Centrifugal force is an inertial force that acts on all objects rotating around an axis. It is the same compressing force you feel in many carnival rides or when you make a u-turn in your car, and is a very energy efficient method of compression.

A common centrifugal force experiment is to take a bucket of water and, with a straight arm, quickly rotate at the shoulder and swing the bucket upward and around a vertical loop. Centrifugal force compresses the water enough to counteract gravity so that even when the bucket it upside-down, the water stays in the bucket.

Centrifugal compressors take this force one step further with expelling the gases out at a specific point in the radial spin. This is best explained by imagining a ball at the end of a rope. If you were to swing the rope vertically around an axis (your hand) at a high velocity, centrifugal force will be pulling the ball outward. When that rope is released at the correct angle, the ball will exit the loop at a high speed and be hurled upward.

Parts of a Centrifugal Compressor

Basic centrifugal compressors are made from 4 main components: an inlet, impeller, diffuser, and collector.

Inlet

An inlet is a pipe in which the gases enter the compressor. Some inlets are open and simple, others contain valves or channels to direct flow in the direction needed inside the compressor.

Impeller

Impellers are the key component in generating centrifugal force. Rotors with carefully angled vanes or blades spin and raise the energy of the gases inside the compressor.

Diffuser

These high velocity fluids or gases are thrown outward and hit the diffuser which converts the kinetic energy into pressure by reducing the velocity.  Diffusers accomplish this in a variety of ways, such as channels or wedged vanes for the high velocity substance to compress against.

Collector

The collector is an empty chamber which gathers the flow coming out of the diffuser. The shape of a collector varies greatly but typically resembles a nautilus shell so it can collect around the entire radius of the impeller and diffuser. Collectors can also sometimes contain valves or other components.

Chilling Solutions

Industrial chillers and their components should be carefully selected so they are ideally situated for the application at hand. Understanding the function and benefits for different compressors can help you find a tailor made chilling solution for your needs.

Chilling Solutions From North Slope Chillers

North Slope Chillers offers easy to install, portable chillers that won’t disrupt your current setup. Contact us to find the chilling solution for your needs:

(866) 826-2993 [email protected]

What Are Cooling Chambers?

Cooling chambers are anodized aluminum storage racks that are specifically designed to store and transfer sensitive liquids. They have grids of wells that can safely house configurations of different sized test tubes and vials while they are being chilled. The anodized aluminum prevents corrosion and ensures cold temperatures are sustained in each lab sample.

What Are Cooling Chambers Used For?

Aluminum cooling chambers are used in many different laboratory applications as samples are put through a process called thermal cycling.

Thermal Cycling

Clinical laboratory research requires meeting exact temperatures for exact periods of time in order to produce accurate results. Thermal cycling exposes reactants to repeated cycles of heating and cooling to start, stop, suspend, or stabilize chemical reactions. One of the most common uses for thermal cycling cooling chambers is a method called PCR (Polymerase Chain Reaction).

PCR

PCR was developed in 1993 by Kary Mullis as a precise method for copying strands of DNA. DNA strands are suspended in tubes of liquid and housed in aluminum cooling chambers while they are thermally cycled. The DNA goes through anywhere from 20-40 different temperature stages causing it to melt, elongate, bind, and reform as needed. Thermal cycling for PCR has become critical to many different industries from medical research to forensic analysis.

How Are Cooling Chambers Thermally Cycled?

Cooling chambers can be housed in many different types of containers as they hit their required temperature targets. These containers range from large fridge-like chambers that are specially calibrated for thermal cycling to small foam ice-chest sized boxes with cooling blocks that can be stored on a counter top.

Total Temperature Control From North Slope Chillers

North Slope Chillers offers portable, easy to install chillers that won’t disrupt your current setup. For more about our temperature control products, contact us: (866) 826-2993 or [email protected].

Fermentation containers come in all shapes and sizes: from massive steel chambers, to medium conical fermenters, all the way down to small car-boy fermenters for small batches and home brewing.

The methods of cooling these chambers are as varied as the fermentation containers themselves. These chilling methods can be approached from two directions: inside or outside.

Cooling From The Inside

Some fermentation chillers involve inserting a cooling rod or coil down into your fermenting liquid. These devices then cool the liquid through direct contact. Cooling a fermentation container from the inside comes with added risks. Anytime a tool or device is inserted into your fermenting liquid, you risk exposure to unwanted microorganisms (such as wild yeasts) that can alter flavors, as well as bacteria, potentially tainting your drink. Opening a fermentation chamber to insert cooling devices also increases the change of oxidization spoilage.

Using this cooling method also greatly decreases the chilling efficiency. Fermentation liquid is exposed to a much smaller cooling surface area, leading it to not cool as effectively, especially for medium to large batches. This also increases the risk of hot and cool spots in the fermenting liquid, making it harder for the yeast to finish the fermentation process.

Cooling From The Outside

Chilling fermentation chambers from the outside is the most effective method. No matter the diameter of your fermenting container, the outside surface area will always be greater than cooling from the inside. Putting the chilling source in direct contact with the fermentation container will produce the best results due to uniform thermal flow from the container to the chiller. As fermenters come in all shapes and sizes, cooling sources should be as flexible as possible to ensure complete contact with the container.

North Slope Chilling Solutions

Fermentation cooling jackets that completely wrap around your fermenter will give you the most direct cooling contact. Insulated Fluxwrap jackets from North Slope Chillers have multiple channels of cooling liquid evenly distributed around your fermentation chamber. Their adjustable temperature range will eliminate hot or cold spots and keep your yeast happy and fermenting. Fluxwrap is easy to install without opening your fermenting container and flexibly fits a wide variety of container shapes and sizes.

Contact us to find the right fermentation cooling solution for your needs:

(866) 826-2993 [email protected]

Fermentation Stage

So you have carefully selected your grains, mashed them, malted them, turned them into wort, and cooled your liquid wort so it is ready to be pitched to your yeast. The most crucial part of the brewing process is about to begin…fermentation. The fermentation stage is a tricky one, in that it can ruin all your hard work leading up to this point if your brew’s environment is not carefully protected.

The most important environmental factor in fermentation is temperature.  Under the right conditions, yeast will wake up, consume the sugars in your wort, and turn them into alcohol and carbon dioxide.  Under the wrong conditions yeast that is too cold will go dormant and not finish fermenting; yeast that is too hot will produce off flavors and aromas or even die off completely.

Enter Fermentation Chambers

Fermentation chambers are specially designed containers to protect the environmental conditions while your brew ferments.  They not only protect your brew’s temperature, but reduce exposure to excess oxygen and unwanted pathogens.

There are many different fermentation chambers used by home brewers. They vary widely depending upon batch size, cost, how much brewing space you have, and how much of your time and energy they consume. Since fermentation is an exothermic process, your brew will continuously generate heat as it ferments.  So how do you keep your fermentation temperatures in the ideal zone without babysitting your brew around the clock? The solution is a fermentation chiller.

Son of a Fermentation Chiller

Home brewers use many methods to chill their fermentation chambers and one of the more popular DIY methods is to construct a “son of a fermentation chiller.”

First designed by home brewer Ken Schwartz in 1995, the whimsically named son of a fermentation chiller has become a common creation among American home brewers. The plans have been redesigned through the help of feedback from other home brewers, but the basic concept is the same.

This fermentation chiller involves building a chamber made of thick insulation foam boards. The brew is housed inside next to rotating jugs of ice, a fan, and thermometer.

Weighing Pros and Cons

Cost

One of the most appealing aspects of the son of a fermentation chiller is the cost. Low cost materials can be easily purchased and if you possess basic construction skills, it can be easily assembled. 

There may be additional costs in the future such as purchase of a second thermometer to make sure you are not just measuring the air temperature inside, but the temperature of your brew itself.

However, cost is only 1 of the factors to consider when looking at your home brew fermentation options.

Batch Size

The larger your brew batch, the more heat will be generated by the fermentation process. The son of a fermentation chiller can be adapted to accommodate up to 7 gallons, but for larger batches, fans and ice will not be sufficient to protect your brew from thermal stress.

Cooling Power

The appeal of buying a small fan to save upfront costs can cause problems in the future. Make sure you have enough cooling power to handle a large, constantly self-heating container of wort.

Time and Energy Consumption

Before home brewing, you need to carefully look at how much time and energy you have available to switch out frozen jugs as they melt and need to be replaced.

Using the son of a fermentation chiller also means spending time carefully monitoring your thermometer.

Space Available

When using a son of a fermentation chiller, the footprint of the chiller may be small, but you will need ample freezer space to store your rotating frozen jugs.

Ease and Peace of Mind

Picture how you would like your home brewing experience to pan out. Balancing work and effort with the enjoyment of sharing your batch with your family and friends is an important aspect of home brewing. Investing in a home brew system can provide long term enjoyment if you carefully weigh your chilling options before hand.

North Slope Chillers Solutions

Be sure to look at the whole picture when embarking upon your home brewing journey.  Low cost options seem convenient at first, but can lead to frustrations in the future. Using a reliable fermentation chamber chilling jacket, and fermentation chillers can save you time, energy, and provide more consistent brewing results.  North Slope Chillers Fluxwrap jackets and fermentation chillers can transform you from home brew babysitter, to home brew master.

Contact us to find the right fermentation chilling solution for your needs:

(866) 826-2993 [email protected]