System Design Options

For more information, refer to ARI Standard 550/590-2003, Performance Rating of Water Chilling Packages Using the Vapor Compression Cycle and the ARI Standard 560-2000, Absorption Water Chiller and Water Heating Packages. Both are published by the Air- Conditioning, Heating, and Refrigeration Institute. www.ahrinet.org

There are many chilled-water-system design options; however, in a basic sense, each option is a function of flow, temperature, system configuration, and control. This section discusses the effect of flow rate and temperature decisions.

It is important to remember that temperatures and flow rates are variables. By judicious selection of these variables, chilled-water systems can be designed to both satisfy chilled-water requirements and operate cost effectively.

Chilled-water systems are often designed using flow rates and temperatures applied in testing standards developed by the Air-Conditioning, Heating, and Refrigeration Institute (AHRI), ARI 550/590–2003 for vapor compression chillers and ARI 560–2000 for absorption chillers (see sidebar). These benchmarks provide requirements for testing and rating chillers under multiple rating conditions. They are not intended to prescribe the proper or optimal flow rates or temperature differentials for any particular system. In fact, as component efficiency and customer requirements change, these standard rating conditions are seldom the optimal conditions for a real system, and industry guidance recommends lower flow rates with resultant higher temperature differences. There is great latitude in selecting flow rates, temperatures, and temperature differences.

Selecting Chilled- and Condenser-Water Temperatures and Flow Rates

Leaving chilled-water and entering condenser-water temperature selection can be considered independently of their respective flow rates. However, temperatures and flow rates should be selected together to design an efficient and flexible chilled-water system.

Guidance for Chilled- and Condenser-Water Flow Rates

The ASHRAE GreenGuide 8 (pp 146-147) states:

In recent years, the 60% increase in required minimum chiller efficiency from 3.80 COP (ASHRAE Standard 90-75) to 6.1 COP (ASHRAE Standard 90.1-2004) has led to reexamination of the assumptions used in designing hydronic media flow paths and in selecting movers (pumps) with an eye to reducing energy consumption… Simply stated, increase the temperature difference in the chilled water system to reduce the chilled-water pump flow rate…

The CoolTools™ Chilled Water Plant Design Guide recommends starting with a chilled-water temperature difference of 12°F to 20°F [7°C to 11°C], and it

SYS-APM001-EN

Chiller System Design and Control

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Trane SYS-APM001-EN manual System Design Options, Guidance for Chilled- and Condenser-Water Flow Rates
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SYS-APM001-EN specifications

The Trane SYS-APM001-EN is an advanced control system designed for HVAC (Heating, Ventilation, and Air Conditioning) applications, specifically tailored to enhance energy efficiency and system performance. This comprehensive solution integrates cutting-edge technologies to optimize climate control in commercial and industrial environments.

One of the main features of the SYS-APM001-EN is its intuitive user interface. The system is equipped with a large, easy-to-read display that provides real-time data on system performance, energy usage, and environmental conditions. This user-friendly interface makes it simple for operators to monitor and adjust settings, ensuring optimal comfort levels and efficient energy consumption.

Another key characteristic of the SYS-APM001-EN is its advanced data analytics capabilities. The system collects and analyzes data from various sensors throughout the building, providing insights into occupancy patterns, equipment performance, and energy consumption trends. This data-driven approach allows facility managers to make informed decisions about system adjustments, predictive maintenance, and energy savings.

The SYS-APM001-EN also boasts robust integration capabilities. It can seamlessly connect with a variety of building management systems (BMS) and other third-party devices. This interoperability enables a cohesive operational ecosystem where HVAC systems can communicate and cooperate with lighting, security, and fire safety systems, enhancing overall building efficiency.

Energy efficiency is a hallmark of the SYS-APM001-EN, as it implements sophisticated algorithms to optimize system operation. These algorithms adjust equipment performance in real-time based on current conditions, thereby reducing energy waste and lowering operational costs. The system is designed to support multiple energy-saving strategies, including demand-controlled ventilation and optimal start/stop scheduling.

Additionally, the SYS-APM001-EN is built with scalability in mind, accommodating facilities of various sizes and configurations. Whether it’s a small office building or a large industrial complex, the system can be tailored to meet specific needs, ensuring that HVAC performance aligns with operational goals.

In conclusion, the Trane SYS-APM001-EN is an innovative HVAC control solution that emphasizes user experience, data-driven decision-making, and energy efficiency. With its advanced features and technologies, it is an essential tool for optimizing building performance and enhancing occupant comfort while reducing environmental impact.
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