(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, building facility techs

Psychrometrics Part #1 mentioned and demonstrated the psychrometric chart “is HVAC.” The chart is a necessary tool for determining the properties of air at various conditions called “state points” and graphically illustrates the energy (enthalpy) present within given samples. Part #1 also provided term definitions for each state point; i.e. dry bulb and wet bulb temperatures, dew point, specific humidity, relative humidity…etc. Psychrometrics Part #2 will provide a brief review of these terms and begin where the previous session ended before examining in greater detail how tempered air properties change and energy is impacted systematically throughout the air conditioning process for the HVAC systems listed below.

Topics to be covered are:

• A brief review of psychrometric terminology
• Applying ASHRAE’s psychrometric graphics, illustrate outside air and building air state points and mixed-air condition for Sonoran Desert
• Demonstrate the psychrometric process of conventional medium pressure VAV systems and VAV box reheat enthalpy gain
• Demonstrate the psychrometric process of humidity control using conventional a supply air condition during Sonoran Desert monsoon
• Demonstrate the psychrometric process for sensible and enthalpy heat recovery units
• Demonstrate the psychrometric process for AHUs serving displacement ventilation systems
• Demonstrate the psychrometric process of DOAS DX AHUs for effective dehumidification and improved thermal comfort

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building facility techs

Building HVAC systems consume approximately 40% of a building’s total energy usage. It requires a lot of energy to condition a building, i.e. to remove heat energy from inside of a building to outdoors (cooling) in summer or to add heat energy (heating) in winter. This presentation reviews the fundamentals and principles of HVAC systems and why building thermal comfort and indoor air quality is necessary to promote human health and well-being. It will also define heat transfer terms and modes, and review ASHRAE Standard 55 design factors to be accounted for to achieve and maintain building thermal comfort.

 Topics to be covered are:

• HVAC: Purpose and Objectives
• Thermal Comfort: Definitions
• Factors of Thermal Comfort (ASHRAE Standard 55)
• Criteria for Thermal Comfort
• Modes of Heat Transfer
• Heat Transfer Mediums
• Introduction to Relevant ASHRAE Standards

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, mechanical and general contractors, building facility techs

The EPA, CDC and ASHRAE advocate for HVAC systems to provide a minimum of outside air in accordance with ASHRAE Standard 62.1’s ventilation requirements to reduce the risk of pathogenic infection. However, they also state increasing the amount of OSA above minimum flow rates is a better solution implying 100% OSA systems offer the a very effective solution. The problem, there is an operational cost premium for increasing OSA flow rates for conventional HVAC systems. However, paying an energy penalty for increasing OSA is not a necessary foregone conclusion. 100% OSA systems can be designed to supply minimum OSA to each zone, or possibly more air, while realizing up to 20% to 30% energy savings for new or retrofit construction with the added benefit of reducing mechanical system footprints.

Topics to be covered are:

• EPA, CDC and ASHRAE Statement Review regarding Outside Air
• Ventilation & Improving Building Indoor Environmental Quality (IEQ)
• Humidity: Control & Impact on Human Health
• HVAC Fundamentals: Building Heat Transfer Review
• Heat Transfer Mediums: Mediums Density and Efficiency
• Dedicated Outside Air Handlers (DOAS): Heat Recovery, & Efficiency
• Increased System Efficiency Options
• 100% OSA Systems: Architectural Advantages

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, building facility techs

100% outside air systems using active chilled beams are a proven HVAC concept that results in 30% or more energy savings than all-air systems. Decoupling sensible and latent loads locally at each zone and shifting the sensible load to a chilled water loop requires less pumping horsepower than would otherwise be required for fans serving all-air systems. Laboratories, that often require high air change rates to maintain occupant safety and have high sensible loads requiring six or more air change rates per hour depending on the number of fume hoods and type of equipment located in a lab. Consequently, adopting chilled beams as a heat transfer solution local to each zone, decoupling and driving the space sensible load to a chilled water loop, is a very efficient way to maintain space design conditions while promoting a healthy work environment for lab technicians and students.

Topics to be covered are:

• 2019 ASHRAE Handbook: HVAC Applications – Chilled Beams
• HVAQ Fundamentals and Heat Transfer
• Conventional Mixed-Air Systems
• Chilled Beams: Concept, Operation and Design
• Passive and Active Chilled Beams: Two Design Strategies
• Chilled Beam Product Portfolio
• Laboratory HVAC Design
• Laboratories and Ventilation Rates
• Fume Hoods and Airflow Control
• Speed of Response
• Applied Chilled Beams for Labs: A Design Approach

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners

ASHRAE’s Epidemic Task Force (ETF) became a leading resource for building owners and design teams to reduce the risk of pathogenic infection. Task force guidelines listed a number of best practices for reducing the risk; increasing outdoor air infraction rates, increasing building filtration effectiveness, maintaining building humidity levels to between 40% to 60% RH, apply UV-C light technology and consider air diffusion patterns within the occupied space. Increasing outdoor air infraction rates has long been acknowledged as an effective way to improve indoor air quality. Why? One reason is expressed on the Environmental Protection Agency’s (EPA) web page, Why Indoor Air Quality is Important to Schools. The page’s Overview states. However, increasing outside air in conventional HVAC designs is operationally expensive, thereby challenging building efficiency targets called out in recent editions of ASHRAE Standard 90.1.

Topics to be covered are:

• Application of ASHRAE ETF guidelines to promote healthier buildings.
• Pros and cons of recommended HVAC best practices.
• Review environmental factors that contribute to infection during cold and flu season and the myth of a well-mixed environment
• Innovative HVAC design strategies that bridge the divide implicit in ASHRAE’s developing IAQ guidelines and decarbonization initiatives

• AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, building facility techs

The Sonoran Desert is known for having a dry heat, yet controlling humidity continues to be problematic for building owners especially during monsoon season. To control humidity, building design teams must understand the physics of water vapor. Conventional HVAC systems supplying air at 55F DB / 54F WB in our Sonoran Desert climate zone will dehumidify at a cooling coil, but often fail to control building humidity levels during Arizona’s monsoon or in other geographical areas with high humidity levels. Understanding the terms and properties of water vapor is essential to maintain proper building humidity control, especially when high-performance HVAC systems are being considered.

Topics to be covered are:

• Fundamentals of HVAC Systems: Review
• The Nature of Water
• The States of Water
• Terms and Definitions
• The Physics of Water Vapor (Every Architect Should Know)
  • Dan’s Home Office and Water Vapor Flow: Wet Moves to Dry
• ASHRAE: Position Document on Infectious Aerosols
• Humidity: Toward healthier environments
• Humidity: Reducing the risk of infection
• AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, building facility techs

ASHRAE Standard 62.1 (Ventilation for Acceptable Indoor Air Quality), a standard adopted by most municipal code authorities, acknowledges displacement ventilation improves a building’s indoor air quality. Supplying air at elevated temperatures (~63-65F) and at low velocity through low in-wall diffusers, or underfloor air devices, results in a thermally stratified environment where convection is the heat transfer mode in a space (i.e. warm air rises, cold air falls), not fan energy required to inject high velocity air. Air movement results when thermal plumes occur around heat sources (i.e. human occupants, lighting, PCs). Clean, conditioned air continually flows across occupant breathing zones as warm contaminated air is drawn vertically across the source and lifted to upper room levels where it is exhausted from a space. Properly designed displacement systems are also more energy efficient compared to conventional mixed air systems.

Topics to be covered are:

• The Physics of Room Air Flow
  • Mixed Air Systems (Review)
  • Thermally Stratified Environments
• Displacement Ventilation: Cooling and Heating
  • The Terminal Diffuser and Control
  • Air Handler Configurations
• Innovative Solutions: Introduction into 100% OSA Systems
• Indoor Air Quality and the Risk of Infection

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, contractors, building facility techs

Conventional HVAC systems maintain building thermal comfort and humidity using an all-air heat transfer approach. To meet building design requirements defined by ASHRAE Standard 55, varying supply air flow to each zone, depending on space load, is a common and cost effective design strategy. Known as variable air volume (VAV) systems, these designs maintain thermostat space temperature set points by regulating airflow supplied from VAV boxes to areas referred to as zones. As VAV box airflow increases or decreases to meet summer or winter conditions throughout a day, main duct static pressures must be controlled to assure all VAV boxes have sufficient air available to meet each of the zone loads. Duct pressure sensors serve to regulate VAV air handler airflow rates by modulating fan speeds to maintain duct pressure at a given set point.

Topics to be covered are:

• A brief history of HVAC
• The relationship of pressure and airflow
• Airflow measurement and flow control of VAV boxes
• VAV box reheat and reheat coil options and control
• Single inlet VAV boxes and construction options
• VAV airflow measuring devices and “k-factors”
• Main duct static pressure control
• VAV air handler fan operation and the principles of “Fan Wall” technology

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, contractors, building facility techs

Passive radiant cooling and heating technologies are similar to active beams by decoupling a building’s sensible and latent loads, but fundamentally different from active designs in how supply air is delivered to a space. By exploiting the physics of convection, the airside component of passive designs create thermally stratified environments resulting in enhanced thermal comfort and IAQ at occupant breathing zones. Passive radiant designs also minimize thermal comfort complaints resulting from radiant heat energy by reducing wall surface temperatures during warm summer months. Another efficiency advantage of passive systems is achieved by applying displacement ventilation as the air delivery method that exploits the benefits of thermally stratified environments.

Topics to be covered are:

• Decoupling the Thermal Load: Sensible and Latent Load Review
• Thermally Stratified Environments: Review
  • Superior Indoor Air Quality and Why
• Passive Beam and Radiant Cooling and Heating Products:
  • Architectural Features and Design Considerations
• The 100% OSA air handler: Brief Review
• Humidity Control: Brief Review
• Energy Efficiency and Passive Systems: More Efficient?
• Chiller Performance: Optimizing Efficiency

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, general and mechanical contractors

To design high-efficiency HVAC systems, it is necessary to control a building’s space air conditions local at each zone. As room loads fluctuate, depending on the type of zone conditioned and its location, a system should respond (modulate) in a manner that consumes only as much energy required to meet each respective zone load. Variable refrigerant systems, commonly known at VRF, are an all-electric mechanical system that accomplishes this objective. By supplying only the amount of refrigerant required to satisfy space load, condenser work is minimized and system efficiency enhanced. However, in our Sonoran Desert climate zone, conventional VRF layouts are often not designed to deliver the type of efficiency available to the technology. To enhance performance, decoupling the outside air from a VRF layout delivers improved system efficiency while creating superior building IAQ. And, since these are all electric systems, they support the AIA’s 2030 Commitment initiatives.

Topics to be covered are:

• Indoor Air Quality: Institutional Initiatives (EPA, CDC, ASHRAE)
• Variable Refrigerant Technology:
  • Condenser and Air Handler Operation and Performance
• Variable Refrigerant Design Considerations
• Optimizing Variable Refrigerant Systems: 100% OSA Concept
  • Three System Design Concepts: Performance and Review
• Architectural Considerations

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners

Hydronic active chilled beam systems are becoming more widely accepted as an energy efficient mechanical option for medium to large scale buildings. Active chilled beam designs can save 30% or more energy when compared to conventional medium pressure VAV systems. By shifting a buildings sensible load to a more dense heat transfer medium (water) local to each zone, HVAC system efficiency is increased. Building supply air flow rates are often designed close to ASHRAE Standard 62.1 minimum ventilation rates, resulting in fan energy and system operating cost reductions. And since these systems are 100% outside air and offer no return air path to a building, they are conducive to creating healthier built environments while reducing the risk of infection.

Topics to be covered are:

• Active Chilled Beam Systems: Design Objectives and Considerations
• Sensible & Latent Loads: Decoupling the Load & What it Means
• Active Chilled Beams: Operation & Design Considerations
• Active Chilled Beams: Mixed-Air Environment (Review)
• Humidity Control: Review
• Air Handler Layout: DOAS – Dimension & Weights
• Enhanced Energy Efficiency: Innovation to Optimize Performance
• Chilled Water Central Plants: Is Water Cooled Necessary Today?

• AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, mechanical and general contractors

As ASHRAE Standard 62.1 attests, thermally stratified environments create superior indoor air quality by drawing a single path of clean air across occupant breathing zones. Underfloor HVAC systems (UFAD) offer an ideal method for creating such an environment. Supplying air through underfloor air diffusers allows the force of convection (warm air rises, cold air falls) to generate a single piston of clean conditioned air to rise from floor planes to upper room levels where it is exhausted from a space. UFAD HVAC systems are low static systems that reduce fan horsepower. In Maricopa County, economizer hours can be doubled as supply air temperature is increased. Recent UFAD technology provides building owners the opportunity to reduce floor to floor heights by designing with lower floor plenum depths of 10” or, possibly, less with the added advantage of reducing churn costs.

Topics to be covered are:

• Thermally Stratified Environments: Review
• Underfloor Air Systems (UFAD)
• UFAD Design Considerations
  • Semi-Turbulent & Displacement Ventilation
  • The Perimeter Zone
  • Plenum Pressure & Temperature: The Importance of Uniformity
  • Supply Air Design Conditions & Why
• UFAD Air Handler Configurations
• Plenum Leakage: Strategies to Avoid the Issue

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building owners, contractors, building facility techs

The federal government and ASHRAE continue to advocate for building designs that consume less energy, provide improved thermal comfort and maintain better “Indoor Environmental Quality” (IEQ). To succeed in achieving these goals, it is essential design teams understand the properties of air and how HVAC systems play a key role in meeting these stated objectives. The psychrometric chart is a primary tool for determining these properties at various reference points called “state points”, the energy contained within a sample of air at given conditions and to apply and evaluate system processes required to maintain humidity and thermal comfort. The psychrometric (“psych”) chart is viewed by many to be HVAC.

Topics to be covered are:

• Provide a brief history of the psych chart
• Review terms and definitions relevant to the use of the chart
• Deconstruct the chart to locate and examine which lines illustrate various air property “state points” and then rebuild it
• Define enthalpy (total load in Btus) and illustrate how to reference it
• Review how a psych chart can illustrate system processes required to move energy from pre- to post- air “state points”, an understanding necessary to properly size equipment to meet building’s total loads.

(1) AIA HSW/LU credit will be available for attending registered architects or (1) PDH for professional engineers.

Recommended Audience: ASHRAE members, mechanical engineers and designers, architects, building facility techs