A critical part of many manufacturing processes is the creation of ideal conditions for the completion of a product. In several cases, those conditions depend on lowering the temperature in a controlled environment to produce the exact conditions that will preserve, initiate, or create the requirements to produce a product. The device that manufacturers use is referred to as a chiller, which are produced using technically advanced sealed chambers with digital temperature controls for precision processing.
What are Chiller Systems?
A chiller system is designed to remove heat by circulating heat absorbing refrigerant through a series of tubes into which heat is absorbed and released. The basic components of a chiller system are its compressor, condenser, expansion valve, and evaporator. Each of these elements work together to circulate the refrigerant and remove heat from the system.
The term chiller system covers a wide range of different cooling systems that come in various sizes to fit the needs of any application. The different types of chillers rely on the use of water or air as a means for removing heat from the system. In an air cooled system, air is circulated by a fan over tubes containing the refrigerant to remove heat and expel it into the atmosphere. With a water cooled system, water from a cooling tower is used to remove heat.
Each of the four components of a chiller have their distinct function and vary slightly between the different designs. One major differentiating factor is the compressor, which is used to compress the refrigerant to return it to liquid form. Although the function of all compressors is the same, there are variations between the types in how they perform their function.
The components of a chiller system vary with manufacturers having proprietary processes designed for their chillers. Regardless of these differences, chiller systems are an ideal tool for keeping processes, operations, and procedures at the correct temperature, without failure.
How Do Chiller Systems Work?
All of the varieties of chiller systems produce the same results with their unique characteristics. The chiller system process follows four steps where the refrigerant that collects heat from a process and removes the heat in the chiller. In all cases, the refrigerant circulates through the chiller chamber in tubes where it collects heat that it brings to the four components of the chiller.
A chiller system works on the concept of vapor compression or vapor absorption to provide a continuous, uninterrupted flow of coolant at a preset temperature.
Evaporator – The evaporator functions as a heat exchanger that transfers the heat captured by the process flow to the refrigerant. During the heat transfer to the refrigerant, the refrigerant evaporates and changes from a low pressure liquid into a vapor, which reduces the temperature of the process coolant.
Compressor – In many ways, the compressor is the heart of a chiller system since it performs many functions in the cooling process. It receives the refrigerant from the evaporator and ensures that the pressure remains low enough to absorb heat. As the refrigerant passes through the compressor, the applied pressure increases such that the temperature of the refrigerant remains constant.
Condenser – In the condenser, the refrigerant is transformed from a vapor to a liquid. During the transformation process, the vapor releases the stored heat that is removed by a water cooled system or air cooled system.
Expansion Valve – The expansion valve, or thermostatic valve, controls the amount of refrigerant that moves from the condenser to the evaporator. They assist in changing the liquid refrigerant under high pressure from the condenser into a gaseous state in the evaporator. Expansion valves prevent the evaporator core from overheating and damaging the efficiency of the chiller system.
The process, as described here, happens efficiently and quickly as a constant and continuous flow. Each part of the process is carefully monitored and controlled to ensure accurate cooling.
Different Types of Chillers
The main types of chillers fall into three categories, which are air cooled, water cooled, and glycol with water cooled chillers being the most common type used. Each of the types have their advantages and operate on the principle of removing heat. The difference between them is how they complete the process.
Air Cooled Chillers
The function of air cooled chillers is to transfer heat from fluids or water. They use a refrigerant that is transformed into a vapor that is removed by a circulating fan. A concern for air cooled chillers is their environmental impact and damage to the ozone layer. To answer this concern, manufacturers use Environmental Protection Agency (EPA) approved refrigerants.
Water Cooled Chillers
A water cooled chiller removes heat and sends cooled water back to the operation, equipment, or process. They are a constantly circulating system that assists in maintaining production efficiency. Water cooled chillers have a small footprint, which makes it possible to install them indoors. Having a chiller stored indoors away from the elements, decreases maintenance costs associated with the weather.
A glycol or low temperature chiller funnels a glycol and water coolant mixture from the refrigeration unit through thermal heat exchanger piping, absorbing heat from the industrial process and warming the coolant. The warmed coolant returns to the refrigeration unit to repeat the cooling process. The process lowers the temperature in a short period of time, depending on production needs.
Glycol is a colorless and odorless fluid used in antifreeze and cooling systems. It can rapidly absorb heat and release it without changing its temperature, which makes it ideal for use with chillers.
How to Choose Your Next Chiller
Chillers provide cooling and heat removal for a wide variety of industries, applications, and processes. A properly sized chiller increases the efficiency of a process, speeds up production, enhances accuracy, protects equipment, and reduces electrical and water consumption.
As with any form of large equipment, the selection of a chiller is a major investment that requires careful consideration. The size of a chiller has to precisely fit the needs of an operation or application to avoid losses and increased costs. Four factors for selecting a chiller are:
Required Coolant Temperature – Coolant temperature is measured at the inlet to a process, which is important in regard to how far the coolant travels to the process. The distance traveled by the coolant before the inlet leads to heat gain that can be controlled with insulating the coolant line or positioning the chiller closer to the process.
Heat Load – The heat load is the amount of heat that has to be removed, which is measured in BTUs per hour or watts. The amount of the heat load from a process is normally provided by the manufacturer of a process or can be calculated.
Flow and Pressure of Coolant – The flow and pressure of the coolant are a function of the surface area and heat transfer of the process being cooled. These two factors are critical to the successful operation of a chiller since miscalculation can lead to damage to a process or piece of equipment.
Heat Dissipation – Heat dissipation is in regard to how the heat will be dissipated or removed. Air cooled chillers exhaust heat into the atmosphere through a ventilation system. Water cooled chillers transfer heat to water from a cooling tower.
When making the choice of a chiller, it is essential to contact experts on the cooling process. The time, investment, and possible harm to a system necessitates having all of the required data to make the perfect choice.
Industries that Use Universal Chilling Systems’ Chillers
For over 75 years, Universal Chilling Systems has been assisting a wide variety of industries in supporting, maintaining, and guiding their chiller needs. Our many years of experience have benefited companies in selecting the precise piece of equipment that perfectly meets the needs of their applications. Universal Chilling Systems produces chillers with cooling capacities that range from 5 tons up to 40 tons with 60 tons up to 100 tons being available upon request.
Each and every one of Universal Chilling Systems’ chillers are tested and examined to ensure they will perform up to our exacting standards and requirements.
Universal Chilling Systems, during its over 75 years of serving industry, has worked closely with a wide variety of industries including:
The Plastic Industry
Food and Beverage Processing
As a leader in the chiller industry, we have been able to provide exceptional equipment, service, and guidance to companies that require cooling systems that perform at and above expectations.