SMACNA 65th Annual Convention Wailea, Maui, Hawaii
HVAC Systems Understanding The Basics Thomas E. Glavinich, D.E., P.E. The University of Kansas October 22, 2008
HVAC Systems - Understanding The Basics
Manual Objective
Provide an introduction to HVAC systems for project personnel and others needing a basic understanding of HVAC system operation and components.
Systems Approach To HVAC
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HVAC Contractor Defined HVAC contractor is the firm that is responsible for the installation for the complete HVAC system in accordance with the scope of work defined by the contract documents.
HVAC System Contractor Scope Of Services z
Air Distribution: – Sheet Metal – Air Distribution Equipment
z z z z z z
Piping Insulation Equipment (Wet) Water Treatment HVAC Controls Test & Balance
Self Perform Versus Subcontract
2
HVAC System Contractor: Advantages z z
Establishes Firm As HVAC Expert Perform All Of CSI Division 23: – Greater Control Of Scope – Less Scope Overlaps & Gaps
z
Higher On Food Chain: – First Tier Subcontractor – Closer To $’s
z z z z
Potential Higher Profits Greater Control Of Schedule & Work Sequence More Project Opportunities More After-Installation Service Opportunities
HVAC General Requirements Facility Fuel Systems HVAC Piping & Pumps HVAC Air Distribution HVAC Air Cleaning Devices Central Heating Equipment Central Cooling Equipment Central HVAC Equipment Decentralized HVAC Equipment
HVAC Systems Applications I II III IV V VI VII VIII IX X XI XII XIII XIV
Introduction Basic HVAC Systems HVAC Control Systems Multizone Systems Dual-Duct Systems Terminal Reheat Systems Variable Air Volume Systems Induction & Induction Reheat Systems Special Applications Hydronic Systems Unitary & Heat Pump Systems Cooling/Refrigerant Systems Hydronic Heat Recovery Systems Engineering Data, Tables & Charts
Manual Currently Being Updated
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HVAC Systems: Understanding The Basics
How Will This Manual Be Used? z Chapter
Education Program z Self Study z Reference z Text: Primary Or Supplemental z Combination
HVAC Systems: Understanding The Basics
Chapter Outline I II III IV V VI VII VIII IX X
Introduction To HVAC Systems Properties Of Moist Air HVAC System Basics Unitary HVAC Systems Central Heating Equipment Central Cooling Equipment Hydronic Distribution Systems Air Distribution Systems Central HVAC Systems Control Systems
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HVAC Systems: Understanding The Basics
Chapter I - Intro To HVAC Systems 1.1 1.2 1.3 1.4 1.5 1.6
Introduction What Is An HVAC System? Why Do Buildings Need HVAC? A Brief History Of HVAC Systems HVAC Systems & 21st Century Buildings Overview Of This Manual
HVAC Systems: Understanding The Basics
Chapter II - Properties Of Moist Air 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11 2.12 2.13
Introduction Air Chemistry Air Temperature Air Humidity Evaporation & Condensation Moist Air Properties Psychrometry Heat Transfer Methods Heat Transfer Units Heat Transfer Media Moist Air Energy Content Simple Space Conditioning Processes Practical Space Conditioning Processes
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Air Temperature z What
Is Temperature? z Temperature Scales z Temperature Measurement
Air Humidity z What
Is Humidity? z Humidity Scales z Humidity Measurement
8
Psychrometric Chart
Moist Air Physical Properties z Dry-Bulb
(DB) Temperature z Wet-Bulb (WB) Temperature z Percent Relative Humidity z Humidity Ratio z Dew Point Temperature z Air Specific Volume
9
Moist Air Energy Content z Sensible
Heat z Latent Heat z Enthalpy
Basic Space Conditioning Processes z z z z z z z z
Introduction HVAC System Purpose HVAC Zones & Spaces Airflow Defined Four Variables The Impact Human Comfort Defining Human Comfort Indoor Air Quality HVAC System Energy Use HVAC System Operation Basic HVAC System Mechanical Elements HVAC Controls Space Conditioning Methods Used By HVAC Systems HVAC Sys Categorized By Primary Heat Transfer Media HVAC System Space Conditioning Methods & Categories HVAC System Equipment Location & Heat Transport
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Four Variables That Affect Human Thermal Comfort Temperature z Thermal Radiation z Humidity z Air Speed z
American Society of Heating, Refrigerating, and AirConditioning Engineers, Thermal Environmental Conditions for Human Occupancy, ASHRAE 55-2004.
ASHRAE Comfort Zones
American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Thermal Environmental Conditions for Human Occupancy, ASHRAE 55-2004.
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HVAC System Energy Use z HVAC
System Energy Use z ASHRAE/IESNA Standard 90.1 z Energy Codes & Standards z Green Buildings & HVAC Energy Use
Basic HVAC System Elements z Thermal
Conditioner z Moisture Controller z Air Mover z Air Cleaner
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Basic HVAC System Elements
Space Conditioning Methods z Constant
Air Volume - Variable Temperature z Variable Air Volume - Constant Temperature z Variable Air Volume - Variable Temperature
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HVAC Systems: Understanding The Basics
Section 3.13 - Primary Heat Xfer z z z z z
All-Air HVAC Systems Air-Hydronic HVAC Systems All-Hydronic HVAC Systems Direct Refrigerant HVAC Systems Hybrid HVAC Systems
All-Air HVAC System
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Air-Hydronic HVAC System
All-Hydronic HVAC System
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HVAC Systems: Understanding The Basics
Chapter IV - Unitary HVAC Systems 4.1 4.2 4.3 4.4 4.5 4.6
Introduction Unitary HVAC Systems Characteristics & Use Refrigeration Defined The Refrigeration Cycle Direct Expansion Refrigeration Systems Unitary HVAC System Types
Refrigeration Cycle
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HVAC Systems: Understanding The Basics
Section 4.5.2 Six Primary DX System Components z Compressor z Condenser
Coil z Regulator Valve z Evaporator Coil z Refrigerant Piping z Controls
HVAC Systems: Understanding The Basics
Section 4.6 - Unitary HVAC Systems z z z z z z z
Packaged Terminal HVAC Units Room Air Conditioners Self-Contained Air Conditioners Computer-Room Air-Conditioners Split-System Air-Conditioners Air-Source Unitary Heat Pumps Water-Source Unitary Heat Pumps
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HVAC Systems: Understanding The Basics
Chapter V - Central Heating Equipment 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 5.10 5.11 5.12
Introduction Furnaces Boilers Boiler Sizing Boiler Construction Electric Boilers Condensing Boilers Boiler Auxiliary Equipment Boiler Controls Boiler Water Treatment Solar Energy Heating Systems Combined Heat & Power
HVAC Systems: Understanding The Basics
Chapter VI - Central Cooling Equipment 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10
Introduction Central Cooling Plant Operation & Components Chiller Purpose Refrigeration Cycle Refrigerant Motor-Compressor Units Mech Compressor Operation & Characteristics Absorption Chillers Cooling Towers Evaporative Cooling Systems
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Central Cooling Plant Schematic Diagram
HVAC Systems: Understanding The Basics
Chapter VII - Hydronic Distribution Sys 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9
Introduction Hot Water Distribution System Operation Chilled Water Distribution System Operation Hydronic Distribution System Operating Temps Hydronic Distribution System Arrangements Multi-Loop Hydronic Distribution System Hydronic Distribution System Heat Xfer Mode Convection Terminal Units Hydronic Radiant Heat
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HVAC Systems: Understanding The Basics
Section 7.5 Hydronic Dist Sys Arrangements z One-Pipe
System z Two-Pipe System z Three-Pipe System z Four-Pipe System z Summer-Winter System
Two-Pipe Hydronic Distribution (Direct Return)
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HVAC Systems: Understanding The Basics
Section 7.8 Convection Terminal Units z z z z z z z z z
Air-Coil Units Fan-Coil Units Induction Units Unit Ventilators Radiators Finned-Tube Radiation Heaters Valence Units Convectors Unit Heaters
HVAC Systems: Understanding The Basics
Chapter VIII - Air Dist Systems 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 8.9 8.10 8.11 8.12 8.13 8.14 8.15
Introduction Air Distribution System Purpose Air Distribution System Components Fans Air Handling Units Air Ducts & Plenums VAV Terminal Units Air Outlets & Inlets Air Distribution System Operation Air Distribution System Operating Point Air Distribution System Dynamics System Operating Point & Fan Speed Variable Frequency Drives Air Cleaning Devices Testing, Adjusting, & Balancing
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HVAC Systems: Understanding The Basics
Chapter IX - Central HVAC Sys 9.1 9.2 9.3 9.4 9.5 9.6 9.7 9.8
Introduction Central HVAC Subsystems VAV System Description VAV System Operation VAV Terminal Operation HVAC Systems Incorporating VAV Constant Volume HVAC Systems VAV Versus Constant-Volume
Central HVAC System Block Diagram
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Basic Single-Zone Cooling Only VAV System
HVAC Systems: Understanding The Basics
Chapter X - Control Systems 10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8 10.9 10.10
Introduction Control System Purpose Control System Types Control System Components Thermostat: Simple Control System Sensors Controllers Controlled Devices Building Automation & Control Systems Open-Architecture Control Systems
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