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Duration: 0.39 Hrs
Course Level: Fundamental
Languages: English
Capability: Audio, Video, MobileReady, Responsive
The purpose of a direct expansion, or DX, system is to remove unwanted heat from a space or substance and transfer it to another space or substance. DX refrigeration systems are sometimes called mechanical refrigeration systems because they use mechanical components to remove and transfer heat. They are widely used in refrigerators, freezers, split systems, and package AC or rooftop units (RTUs). When troubleshooting a DX system, check the basics first – superheat in the suction line, subcooling in the liquid line, suction pressure, discharge (or head) pressure, and motor amps – to see if they are in their normal ranges for current conditions. A troubleshooting chart appropriate for your expansion device can provide guidance as to the possible issues. If you can’t pinpoint the problem, there may be an issue with one of the mechanical components. This course covers component issues that can affect the performance of a DX system, including issues with the compressor, compressor motor, expansion valve, refrigerant charge, liquid line, and lubricating oil system. This information, plus experience working around DX systems, will help you troubleshoot problems successfully and in a timely manner.
By the end of this course, you will be able to:
Duration: 0.43 Hrs
Course Level: Intermediate
Languages: English
Capability: Audio, Video, MobileReady, Responsive
The purpose of a direct expansion, or DX, system is to remove unwanted heat from a space or substance and transfer it to another space or substance. DX refrigeration systems are sometimes called mechanical refrigeration systems because they use mechanical components to remove and transfer heat. They are widely used in refrigerators, freezers, split systems, and package AC or rooftop units (RTUs). DX systems use the vapor-compression refrigeration cycle in which a “refrigerant” alternately absorbs and rejects heat as it circulates through four main components – the compressor, condenser, expansion device, and evaporator. The temperature and pressure of the refrigerant can be checked at several locations to monitor system operations and help with troubleshooting efforts. This course discusses how system temperatures, pressures, superheat, and subcooling can be used to monitor the condition of a DX system, help troubleshoot problems, and charge refrigerant. When troubleshooting a DX system, make sure any troubleshooting chart you are using is appropriate for the expansion device, as symptoms differ for fixed orifice devices and TXVs.
By the end of this course, you will be able to:
Duration: 0.47 Hrs
Course Level: Intermediate
Languages: English
Capability: Audio, Video, MobileReady, Responsive
Direct expansion, or DX, systems use the vapor-compression refrigeration cycle to remove heat from enclosed spaces and transfer it to the outside environment. The term “direct expansion” refers to the fact that the refrigerant expands to produce a cooling effect that is delivered directly to the conditioned air. DX systems are used in a variety of applications, including refrigerators, freezers, split systems, and package AC or rooftop units (RTUs). In the vapor-compression refrigeration cycle, a “refrigerant” alternately absorbs and rejects heat as it circulates through the system. The system has four main components – a compressor, condenser, expansion device, and evaporator – and the refrigerant changes pressure, temperature, and phase as it circulates through these components. This course introduces the four main DX system components, including their purpose and design. It also describes several other common system components, temperature-sensing devices, several types of valves, pressure switches, and defrost controls.
By the end of this course, you will be able to:
Duration: 0.46 Hrs
Course Level: Advanced
Languages: English
Capability: Audio, Video, MobileReady, Responsive
Centrifugal chillers are used in medium- and large-sized buildings to provide comfort cooling. Many of them use the vapor compression refrigeration cycle, including centrifugal compressors and plate-and-frame or shell-and-tube heat exchangers, to produce chilled water that can be pumped to AHUs and FCUs located in different spaces. At each AHU or FCU, the chilled water passes through a cooling coil while a fan blows air over the coil to produce cool air for the enclosed space. The chilled water then returns to the chiller unit, where it is re-cooled, and the process is repeated. Like other building systems, chiller systems require regular monitoring and maintenance in order to maintain their capacity and efficiency and avoid costly breakdowns and repairs. This course introduces common chiller types and components, including their purpose and design. Special attention is given to the compressor, which increases the pressure of the refrigerant and prepares it to reject heat in the condenser. It also identifies those items that should be regularly checked for leaks or wear and replaced periodically.
By the end of this course, you will be able to:
Duration: 0.43 Hrs
Course Level: Advanced
Languages: English
Capability: Audio, Video, MobileReady, Responsive
Centrifugal chillers are used in medium- and large-sized buildings to provide comfort cooling. Many of them use the vapor compression refrigeration cycle to produce chilled water that is pumped to AHUs and FCUs located in various spaces around the building. Afterwards, the chilled water returns to the chiller unit, where it is re-cooled, and the process is repeated. Chiller systems are sized to handle the amount of heat that is generated inside a facility. However, cooling loads vary during the day as well as seasonally, and they can change over time as facility uses change. This can make chiller sizing challenging. An undersized system will not be able to be keep up and water temperatures will fluctuate, while an oversized system will cost more initially and not run efficiently. This course defines several chiller performance parameters, including capacity, delta T, and several efficiency factors, and it explains why they are important. It also lists items that should be checked during startups and capacity modulation techniques used during normal operations to ensure the safe efficient operation of chiller systems.
By the end of this course, you will be able to:
Duration: 0.31 Hrs
Course Level: Advanced
Languages: English
Capability: Audio, Video, MobileReady, Responsive
Centrifugal chillers are used in medium- and large-sized buildings to provide comfort cooling. Many of them use the vapor compression refrigeration cycle, including centrifugal compressors and plate-and-frame or shell-and-tube heat exchangers, to produce chilled water that can be pumped to AHUs and FCUs located in different spaces throughout the building. At each AHU or FCU, the chilled water passes through a cooling coil while a fan blows air over the coil to produce cool air for the enclosed space. The chilled water then returns to the chiller unit, where it is re-cooled, and the process is repeated. Like other building systems, chiller systems require regular monitoring and maintenance in order to maintain their capacity and efficiency and avoid costly breakdowns and repairs. However, issues and breakdowns still occur. A good understanding of chiller design and operation is critical when troubleshooting a chiller system. This course discusses some common issues for centrifugal chillers and the troubleshooting steps and techniques that can be used to diagnose and determine the cause if a problem occurs.
By the end of this course, you will be able to:
Duration: 0.43 Hrs
Course Level: Advanced
Languages: English
Capability: Audio, Video, MobileReady, Responsive
Due to the critical nature of server rooms and the dependence that virtually every organization has placed upon them, facility staff must recognize the importance of uninterrupted service from the computers within the server room. This online interactive course is intended for those responsible for maintaining computer room air conditioning systems. It will expand your knowledge of CRAC systems by identifying specific areas where attention should be focused to keep the systems running efficiently and reliably. We will also be discussing a few ancillary systems, which are also critical to the safe and successful operation of server rooms.
By the end of this course, you will be able to:
Duration: 0.50 Hrs
Course Level: Intermediate
Languages: English
Capability: Audio, Video, MobileReady
This course is intended to be a primer to help any system operator or maintenance person to better understand some of the aspects and sometimes subtle nuances of computer room A/C systems, as well as the ancillary equipment and systems which normally support the A/C system. This online interactive course is by no means an in-depth study of computer room A/C systems, but strictly an introduction into the specialized world and nature of computer room A/C systems. By studying the fundamental information presented herein, you will gain enough information to be able to assist in keeping your company’s computers and servers fully, and reliably, operational.
By the end of this course, you will be able to:
Duration: 0.50 Hrs
Course Level: Fundamental
Languages: English
Capability: Audio, Video, MobileReady
Did you know there are two types of cooling systems used in HVAC applications? Cooling systems remove heat from air – sensible heat from the gases in air and latent heat from the water vapor in air – in order to produce the desired temperatures and humidity levels in enclosed spaces. This interactive online course covers sensible heat and latent heat, British thermal units, the three laws of thermodynamics, and the cooling equipment that is used in HVAC systems.
By the end of this course, you will be able to:
Duration: 0.50 Hrs
Course Level: Fundamental
Languages: English
Capability: Audio, Video, MobileReady
Cooling systems remove heat from building air in order to produce the desired temperatures and humidity levels in enclosed spaces. These electro-mechanical systems require routine inspections and maintenance to keep them functioning properly. This interactive online course covers how to inspect and maintain cooling system drive belts, and best practices for greasing bearings and cleaning of cooling system coils.
By the end of this course, you will be able to:
Duration: 0.50 Hrs
Course Level: Fundamental
Languages: English
Capability: Audio, Video, MobileReady
How do you properly cool a building? Cooling systems are used to cool and condition the air in rooms and building. To do this, they must remove heat from the air. How much heat needs to be removed to reach the desired temperature? What about humidity – the amount of water vapor in the air? Humidity affects how much heat we feel so it must also be addressed. This interactive online course will address these and other cooling system-related topics and issues.
By the end of this course, you will be able to:
Duration: 0.50 Hrs
Course Level: Fundamental
Languages: English
Capability: Audio, Video, MobileReady
“Who turned down the thermostat? Why is it so cold in here?” Individuals who respond to hot and cold calls made by uncomfortable building occupants must have a certain set of skills, including a thorough understanding of the heating/cooling system in question, training in problem-solving or troubleshooting techniques, and people skills. This interactive online course will discuss how to methodically approach cooling system-related complaints and problems, as well as desirable personality traits and useful problem-solving techniques for effective customer service representatives.
By the end of this course, you will be able to: