System Design Options

Condenser-Water Temperatures

Today’s chillers can run at various entering condenser-water temperatures, from design temperature to the lowest-allowable temperature for that particular chiller design. However, many existing older chillers are limited in their allowable condenser-water temperatures. Contact the chiller manufacturer for these limits. Optimal condenser-water temperature control is discussed in the section, “System Controls” on page 87.

Chilled- and Condenser-Water Flow Rates

The selection of chilled-water and condenser-water flow rates is a powerful tool that designers have at their disposal. Kelly and Chan10, and Schwedler and Nordeen11, found that reducing flow rates can reduce the costs of chilled-water system installation and/or operation. The ASHRAE GreenGuide8 states, “Reducing chilled- and condenser-water flow rates (conversely, increasing the ΔTs) can not only reduce operating cost, but, more important, can free funds from being applied to the less efficient infrastructure and allow them to be applied toward increasing overall efficiency elsewhere.”

Standard rating flow conditions

Presently, the standard-rating-condition flow rates for electric chillers in ARI 550/590 are:

2.4 gpm/ton [0.043 L/s/kW] for evaporator

3.0 gpm/ton [0.054 L/s/kW] for condenser

This evaporator flow rate corresponds to a 10°F [5.6°C] temperature difference. Depending on the compressor efficiency, the corresponding condenser temperature difference is 9.1°F to 10°F [5.1°C to 5.6°C].

Absorption chillers are rated using ARI Standard 560–2000, Absorption Water Chiller and Water Heating Packages 9. The evaporator flow rates are the same as those used in ARI 550/590; however, condenser (often called cooling water) flow rates differ depending on the absorption chiller design. Table 3 shows the standard rating conditions for various absorption chillers.

Table 3. Standard rating conditions for absorption chillers

 

 

Condenser Flow Rate

Absorption Chiller Type

gpm/ton

L/s/kW

 

 

 

 

Single Effect

3.60

0.065

 

 

 

 

Double Effect

Steam or hot water

4.00

0.072

 

 

 

Direct fired

4.00

0.081

 

 

 

 

 

SYS-APM001-EN

Chiller System Design and Control

29

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Image 35
Trane SYS-APM001-EN Condenser-Water Temperatures, Chilled- and Condenser-Water Flow Rates, Standard rating flow conditions

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.