Trane SYS-APM001-EN manual Preferential loading sidestream arrangement

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Chilled-Water System Variations

One caveat when applying this arrangement is that chillers on the production side of the bypass line will run more often at low part-load conditions. Older chillers or newer chillers with a high cycle point may not have this capability.

Preferential loading - sidestream arrangement

Figure 45. Sidestream preferential loading arrangement

Figure 45 shows a simple modification to the traditional decoupled arrangement. The sidestream arrangement ensures that the chiller piped in the sidestream position still receives the warmest entering-water temperature and can fully load it whenever the chiller plant operates.

Chiller 3

Production

Chiller 2

Bypass Line

Distribution

Chiller 1

Sidestream position receives the warmest return water.

This arrangement is unique because it not only allows preferential loading, but it also permits the cooling device (chiller, heat exchanger, etc.) in the sidestream position to operate at any leaving-water temperature. This configuration precools the system-return water for the chillers downstream, reduces their loads and energy consumption, and decreases the overall operating cost of the chilled-water system.

When cooling devices are located in the return piping of the distribution loop, they do not contribute to system demands for flow. They simply reduce the temperature of return water to the production loop. While this is counterproductive to the principle of striving for the highest possible return water temperature, it is often the best way to obtain free cooling, specialized heat recovery, or reduce the capital cost of ice storage equipment.

Sidestream, decoupled applications are usually most economical when the sidestream chiller is smaller than those on the production side of the bypass line. Since pumping requirements and energy consumption change with modifications to the system arrangement, it is best to use a computerized analysis tool to model the economic effects.

The following are different system configurations that can benefit from the sidestream application.

Sidestream plate-and-frame heat exchanger

A free-cooling heat exchanger may be capable of chilling water to only 48°F [8.9°C] during some periods. Rather than overlook this portion of cooling capacity assistance, the heat exchanger does whatever it can to its portion of the total return stream. Figure 40 on page 70 shows a possible chilled- and condenser-water piping arrangement that allows for simultaneous waterside economizer and chiller operation. Chillers operating downstream can reduce chilled-water temperature further, allowing simultaneous free cooling and mechanical cooling. This configuration increases the hours that the heat exchanger may be used. Since this capacity is brought to bear on the warmest water in the system, it allows the highest heat exchanger effectiveness and has the greatest impact.

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Chiller System Design and Control

SYS-APM001-EN

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Contents May Page Chiller System Design and Control Preface Contents 100 Primary System Components ChillerPrimary System Components Chiller evaporatorEffect of chilled-water temperature Effect of chilled-water flow rate and variationEffect of condenser-water flow rate Effect of condenser-water temperatureWater-cooled condenser Maintenance Air-cooled condenserAir-cooled versus water-cooled condensers Packaged or Split System?Low-ambient operation Energy efficiencyLoads Air-cooled or water-cooled efficiencyThree-way valve load control Two-way valve load controlVariable-speed pump load control Face-and-bypass dampersChilled-Water Distribution System Chilled-water pumpManifolded pumps Distribution pipingPump per chiller Pumping arrangements Constant flow systemCondenser-Water System Cooling towerPrimary-secondary system Variable-primary systemCondenser-water pumping arrangements Effect of load on cooling tower performanceEffect of ambient conditions on cooling tower performance Single tower per chillerRecommended chiller-monitoring points per Ashrae Standard Unit-Level ControlsChiller control Centrifugal chiller capacity control Centrifugal chiller with AFDAFD on both chillers Application Considerations Small Chilled-Water Systems 1-2 chillersCondensing method Application Considerations Constant flowVariable flow Application Considerations Number of chillersParallel or series Part load system operationPreferential vs. equalized loading and run-time Mid-Sized Chilled-Water Systems ChillersManaging control complexity Large chilled-water system schematic Large Chilled-Water Systems + Chillers, District CoolingWater PowerPipe size Chiller performance testing Limitations of field performance testingChiller Plant System Performance ControlsSYS-APM001-EN SYS-APM001-EN System Design Options Guidance for Chilled- and Condenser-Water Flow RatesSystem Design Options Chilled-Water TemperaturesStandard rating temperatures Standard rating flow conditions Condenser-Water TemperaturesChilled- and Condenser-Water Flow Rates System Design Options Selecting flow rates DP2/DP1 = Flow2/Flow11.85 Low-flow conditions for cooling tower Base Case Low FlowTotal system power Component Power kW Base Case Low Flow System summary at full loadCoil response to decreased entering water temperature Chilled water system performance at part loadEntering fluid temperature, F C Cooling-tower options with low flowSmaller tower System designΔT2 = 99.1 78 = 21.1F or 37.3 25.6 = 11.7C Same tower, smaller approachSame tower, larger chiller Same tower, smaller approach Present Smaller ApproachRetrofit opportunities Retrofit capacity changes Larger Present Chiller Same towerCost Implications Misconceptions about Low-Flow Rates Misconception 1-Low flow is only good for long piping runsKWh SYS-APM001-EN System Configurations Parallel ChillersSystem Configurations Parallel chillers with separate, dedicated chiller pumpsSeries Chillers Series chillersPrimary-Secondary Decoupled Systems Hydraulic decouplingCheck valves System Configurations Production Production loopSystem Configurations Distribution Distribution-loop benefits of decoupled system arrangementTertiary or distributed CommonCampus Decoupled system-principle of operation Tertiary pumping arrangementFlow-sensing Temperature-sensingFlow-based control Subtracting a chiller Multiple chilled-water plants on a distribution loopAdding a chiller Pump control in a double-ended decoupled system Double-ended decoupled systemChiller sequencing in a double-ended decoupled system Variable-Primary-Flow Systems Other plant designsAdvantages of variable primary flow Operational savings of VPF designsChiller selection requirements Dispelling a common misconceptionFlow, ft.water Flow rate Managing transient water flows Flow-rate changes that result from isolation-valve operationSystem Configurations System design and control requirements Effect of dissimilar evaporator pressure dropsAccurate flow measurement Chiller sequencing in VPF systems Bypass flow controlAdding a chiller in a VPF system Flow-rate-fluctuation examplesSubtracting a chiller in a VPF system Sequencing based on loadOther VPF control considerations Select slow-acting valves to control the airside coilsPlant configuration Consider a series arrangement for small VPF applicationsGuidelines for a successful VPF system Chiller selectionPlant configuration Bypass flowChiller sequencing Airside controlHeat Recovery Chilled-Water System VariationsCondenser Free Cooling or Water Economizer Plate-and-frame heat exchangerChilled-Water System Variations Refrigerant migrationRefrigerant migration chiller in free-cooling mode Well, river, or lake waterPreferential Loading Preferential loading parallel arrangementPreferential loading sidestream arrangement Sidestream plate-and-frame heat exchangerSidestream with alternative fuels or absorption Chilled-Water System VariationsPreferential loading series arrangement Sidestream system controlSeries-Counterflow Application Series-series counterflowCondensers Unequal Chiller SizingEvaporators Amount of Fluid in the Loop System Issues and ChallengesLow ΔT Syndrome System Issues and Challenges Chiller response to changing conditionsSystem response to changing conditions ExampleType and size of chiller ContingencyMinimum capacity required System Issues and Challenges Location of equipment Alternative Energy SourcesWater and electrical connections Ancillary equipmentThermal storage Plant ExpansionAlternative fuel Flow rate out of range Retrofit OpportunitiesApplications Outside the Chiller’s Range System Issues and Challenges Temperatures out of range Precise temperature controlPrecise temperature control, multiple chillers Chilled water reset-raising and lowering System ControlsChilled-Water System Control Chilled-water pump controlNumber of chillers to operate Critical valve reset pump pressure optimizationSystem Controls Condenser-Water System Control Minimum refrigerant pressure differentialVFDs and centrifugal chillers performance at 90% load Chillers DifferenceCondenser-water temperature control Cooling-tower-fan controlChiller-tower energy balance Chiller-tower energy consumptionSystem Controls Variable condenser water flow Chiller-tower-pump balanceDecoupled condenser-water system Effect of chiller load on water pumps and cooling tower fansCDWP-2 Failure Recovery Failure recoveryConclusion Glossary Glossary Pumps systemGlossary References Plant. Idea 88th Annual Conference Proceedings 1997References Engineering July102 Index AshraeIndex 105 106 Page Trane

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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