System Controls

Chilled-Water System Control

Chilled water reset—raising and lowering

Many chilled-water plants use chilled water reset, that is, the chiller’s leaving- water temperature setpoint, in an effort to reduce chiller energy consumption. This can either be accomplished by the chiller controller or by the system controller.

Raising the chilled-water temperature reduces chiller energy consumption. In a constant-volume pumping system, this may reduce overall system energy consumption as long as humidity control is not lost. Humidity control may be lost if, as chilled-water temperature is increased, the air temperature leaving the coil increases to a point where it no longer performs adequate dehumidification.

In a variable-volume pumping system, however, raising the chilled-water temperature increases pump energy, often substantially, and typically increases total system energy. Before considering increased chilled-water temperature, the system operator should calculate the increased pumping energy and compare it with the chiller energy savings. It should be noted that ASHRAE/ IESNA Standard 90.1–200720requires chilled-water reset for constant-volume systems—with some exceptions—but exempts variable-volume systems from this requirement for the reasons discussed.

An often overlooked method of decreasing system energy consumption is to reduce the chilled-water temperature, thereby decreasing pumping energy but increasing chiller energy. This strategy is possible with adequate chiller capacity and lift capability. Reducing chilled-water temperature may also improve dehumidification in the building. Another result of reducing the chilled-water temperature is increased chiller capacity during times when the condenser water temperature is cooler than design. This allows more time before another chiller and its ancillary equipment are started.

Be aware that any change in chilled-water setpoint requires changes to be made to the system chiller-sequencing algorithms to ensure that system capacity is met. This added complication may not be warranted.

Chilled-water pump control

In constant flow systems, the pumps are either on or off, providing relatively constant flow when turned on. In practice, some flow variation will occur as system pressure drop changes. In a variable-flow system, pump control is most often performed by maintaining a pressure differential at a selected point in the system. For example, a variable-speed drive will increase its speed if the sensed pressure differential is too low, or slow down if the pressure differential is too

SYS-APM001-EN

Chiller System Design and Control

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Trane SYS-APM001-EN manual System Controls, Chilled-Water System Control, Chilled water reset-raising and lowering
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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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