Today’s systems are designed to meet stricter environmental, indoor quality of air and end user requirements. Lots of the gains in HVAC system efficiency have come as a result of advancements in the operating efficiency of key products. Various other gains are the response to the use of technology that are either new, or new to the HVAC field. Even the use of computer-aided design tools have helped system engineers design HVAC systems that perform more skillfully.
Although there are many individual advances which may have helped to improve HVAC system operating efficiency, most of the overall improvement can be attributed to five key factors:
For years, building owners were satisfied with the performance and efficiencies of chillers that operated in the range of 0. 8 to 0. 9 kW/ton when hvac near me. As they age group, actual operating efficiencies fall season to more than one particular. 0 kW/ton at full load.
Today, new chillers are being installed with full load-rated efficiencies of 0. 50 kW/ton, a near fifty percent increase. Evenly impressive will be the part-load efficiencies of the new era of chillers. Although the operating efficiency of practically all older chillers speedily falls off with reduced load, the operating efficiency of new chillers would not drop off practically as quickly.
Chiller design changes
Several design and procedure changes have helped improve chiller performance. To increase the heat transfer characteristics of the chillers, manufacturers have increased how big the units’ heat exchangers. Electromechanical control systems have been substituted by microprocessor-based electronic handles that provide greater accuracy, reliability and flexibility. Changing frequency drives control the speed of the automotive compressor, resulting in a climb in part-load performance.
Raised energy efficiency is not the sole benefit for the new generation of building chillers; these chillers offer better refrigerant containment. Though older chillers routinely may have lost 10 percent to fifteen percent of the refrigerant charge every year, new chillers can limit losses to less than 0. 5 percent. Lower leak rates and better purge systems reduce the level of non-condensable emissions found in the refrigerant system — a vital factor in maintaining chiller performance over time.
Another significant development is in central heating boiler operation: the replacement of pneumatic and manual adjustments with microprocessor-based systems. Because a rule of thumb, the systems can be expected to achieve energy savings of 5 percent to 7 percent over conventional pneumatic-based systems.
Microprocessor-based control systems achieve their savings mostly as the result of their capability to modulate the boiler’s procedure more accurately than pneumatic-based systems. By modulating the boiler’s procedure effectively, the systems help to take care of the proper fuel-to-air rate and track the insert located on the furnace by the HVAC system.
Microprocessor-based systems offer several additional advantages, including remote control monitoring and operating features, automated control sequences, monitoring of steam flow, and reduced maintenance costs. One particular way the systems can help reduce maintenance costs is through their capability to maintain proper fuel-to-air ratio. By maintaining the proper ratio, the systems reduce the rate where soot collects on central heating boiler tubes, thus decreasing the frequency of required eliminate and cleaning. Keeping the boiler tubes clean of soot also helps to increase the thermal efficiency of the boiler.
Direct digital controls
An important change in the HVAC field is the widespread implementation of direct digital controls (DDC). Introduced more than 12-15 years ago, DDC systems have end up being the industry standard for control systems design today. Having the ability to provide accurate and precise control of temp and air and drinking water flows, the systems have widely replaced pneumatic and electric control systems.
DDC systems help building owners save energy in many ways. Their accuracy and accurate practically eliminate the control problems of offset, overshoot, and hunting commonly present in pneumatic systems, resulting in better regulation of the system. Their ability to respond to a pretty much unlimited range of detectors brings about better coordinated control activities. This also allows the systems to perform more complex control strategies than could be performed with pneumatic controls. Finally, their simple or computerized calibration ensures that the control systems will perform as designed over time, with little or no loss of accuracy.
DDC systems also offer several other advantages. Because the control strategies are software-based, the systems can be easily modified to match within occupant requirements without costly hardware changes. DDC systems also are suitable for applications that benefit from remote monitoring and procedure.