energydesignresources - Taylor Engineering

1 Chilled Water PlantDesign GuideDecember 2009energydesignresourcesiCOOLTOOLS CHILLED WATER PLANT design GUIDE - TABLE OF CONTENTSTABLE OF CONTENTS1. Overview .. 1-1 Introduction .. 1-1 Target Audience .. 1-1 Organization of Material .. 1-2 How to Use the Guide .. 1-32. Chilled Water Plant Loads .. 2-1 Understanding Loads and Their Impact on design .. 2-1 Peak Loads Overview .. 2-3 Annual Load Profiles Overview .. 2-4 Oversizing / Undersizing Considerations.

2 2-4 Determining Peak Loads .. 2-6 Calculations/Simulations .. 2-6 Site Measurements .. 2-7 Rules of Thumb .. 2-8 Determining Hourly Load Profiles .. 2-8 Computer Simulation 2-8 Site Measurements .. 2-103. Chilled Water Plant Equipment .. 3-1 Introduction .. 3-1 Water Chillers .. 3-1 Manufacturer Data.

3 3-1 Refrigeration Cycle .. 3-2 Refrigerants .. 3-3 Water Chiller Components .. 3-5 Compressors .. 3-5 Evaporators .. 3-12 Condensers .. 3-14 Safety Controls, Accessories, and Options .. 3-15 Performance Characteristics and Efficiency Ratings .. 3-18 Heat Rejection .. 3-24 Manufacturer Data .. 3-24 Cooling Towers.

4 3-24 Air-Cooled Refrigerant Condensers .. 3-32 Evaporative Condensers .. 3-34 Pumps .. 3-35 Manufacturer Data .. 3-35 Pump Types .. 3-36 Pump Performance Curves .. 3-37 Selecting Pumps .. 3-39 Pump Installation and Operation .. 3-44 Variable-Speed Drives .. 3-44 Manufacturer Data.

5 3-45 Power Quality Issues .. 3-46 Drive System Efficiency .. 3-46 VSD Accessories and Considerations .. 3-47iiCOOLTOOLS CHILLED WATER PLANT design GUIDE - TABLE OF CONTENTS4. Hydronic Distribution Systems .. 4-1 Chilled Water Systems .. 4-1 Introduction .. 4-1 Constant-Flow Chilled Water Systems .. 4-2 Variable-Flow Chilled Water Systems .. 4-7 Variable-Flow System design Considerations .. 4-16 Condenser Water Systems.

6 4-33 Introduction .. 4-33 Choosing the Style of Cooling Tower .. 4-33 Locating the Condenser Water 4-34 Piping Multiple Chillers and Cooling Towers .. 4-36 Piping for Waterside Economizers .. 4-40 Auxiliary Condenser Water Circuits .. 4-42 Piping Heat Recovery Options .. 4-435. Controls and Instrumentation .. 5-1 Introduction .. 5-1 Choosing Instrumentation Control and Monitor Points .. 5-1 Point Justification .. 5-1 Operating Environment for Controls and Instrumentation.

7 5-2 Network Connections to Equipment 5-2 Sensors .. 5-3 Typical End to End Accuracy Requirements .. 5-3 Temperature Sensors .. 5-4 Humidity Sensors .. 5-6 Liquid Flow Sensors .. 5-7 Pressure Sensors .. 5-9 Electric Current Sensors .. 5-10 Electric Power Sensors .. 5-11 Gas Flow Sensors.

8 5-13 Control Valves .. 5-14 Valve Types .. 5-14 Valve Selection Criteria .. 5-15 Controllers .. 5-17 Minimum DDC Controller requirements .. 5-17 Interfacing with Chillers and Chiller Networks .. 5-18 Interfacing with Variable-Frequency Drive (VFD) Networks .. 5-19 Interfacing with Power Metering Networks .. 5-20 Performance Monitoring .. 5-21 Integrating Chiller Plant Efficiency Monitoring with Control.

9 5-21 Local Instrumentation .. 5-22 Evaluating the 5-22 Local Instruments .. 5-22 Pressure and Temperature Test Ports .. 5-22 Control Sequences .. 5-23iiiCOOLTOOLS CHILLED WATER PLANT design GUIDE - TABLE OF CONTENTS6. Optimizing design .. 6-1 design Procedure .. 6-1 Selecting Chilled Water Distribution System Flow Arrangement .. 6-3 Simplified Distribution System Selection .. 6-3 Primary-only versus 6-4 Optimizing Chilled Water design Temperatures.

10 6-7 Recommendations for Selecting design Chilled Water Temperatures .. 6-10 Selection of Condenser Water design Temperatures and Cooling Tower .. 6-11 Tower Fan Speed Control .. 6-12 Tower Efficiency .. 6-14 Tower Range and Approach Temperatures .. 6-16 Tower Flow Turndown .. 6-19 Fine-Tuning Tower Selections .. 6-20 Selecting Type, Number, and Size of Chillers .. 6-20 Optimizing Piping design .. 6-20 Pipe Sizing.