HVAC Made Easy: A Guide to Heating & Cooling Load Estimation

HVAC Made Easy: A Guide to Heating & Cooling Load Estimation

Course Outline

The calculation of the cooling and heating loads on a building or zone is the most important step in determining the size the cooling and heating equipment. Proper sizing of HVAC equipment can mean savings in initial & operating cost of mechanical equipment and increased comfort to occupants. Equipment over sizing causes frequent cycling of equipment and poor dehumidification during cooling months.

This 4- hour course describes the fundamentals of heating and cooling load calculations, load reduction strategies, code references, useful equations and the design decisions that lie behind these equations.

This course includes a multiple-choice quiz at the end, which is designed to enhance the understanding of the course materials.

Learning Objective

At the conclusion of this course, the student will be aware of:

Key definitions and useful terminology
Useful equations and their interpretation
Sensible and latent load components
External and internal sources of heat gain/loss
Thermal transmission through building elements
Solar heat gain/loss through window glazing
Internal heat gain though people, lighting and power equipment
Influence of ventilation & infiltration on load, IAQ and building pressurization
Psychrometric analysis for estimating supply air flow rates
Winter heat load estimation
Load Reduction Strategies - "Architectural & Mechanical Aspects"
Rule of thumbs, standard forms and common software programs

Intended Audience

This course is aimed at students, mechanical and HVAC engineers, architects, building designers, contractors, civil estimators, energy auditors, facility managers and general audience.

Course Introduction

The heating and cooling load for a building is the rate at which heat must be supplied to or removed from it in order to keep the temperature, humidity and air quality within a specified range. This is the load that must be handled by the air-conditioning system. Its magnitude depends on outside climatic conditions, the construction materials, glazing, ventilation rates, lighting, equipment, occupancy and to the great extent; the design of the building.

To improve a building's overall cooling efficiency, it is helpful to understand what sources of heat gain or loss create the greatest cooling or heating load on the air conditioning system. By reducing those loads, air conditioning first costs and energy costs can be lowered and comfort can be improved.

The course reviews the above criteria in detail and is divided into 10 sections:

Part 1 Summer Cooling Load- Basic Concepts
Part 2 Solar Heat Gain through Walls, Roof & Partitions
Part 3 Solar Heat Gain through Glazing
Part 4 Heat Gain through Lighting
Part 5 Heat Gain through Power Equipment
Part 6 Heat Gain through Occupancy
Part 7 Heat Gain through Ventilation & Infiltration
Part 8 Supply Air Estimation
Part 9 Winter Heating Load Calculation
Part 10 Conservation Strategies - Architectural & Mechanical Aspects
Appendix A - Design Factors & Inputs - Standard Forms
Appendix B- Thermal Transmission through Building Elements
Appendix C - Rule of Thumb Figures
Appendix D - Software Programs
Appendix E - Definitions of Useful Terms

Course Content

The course content is in a PDF file HVAC Made Easy: A Guide to Heating & Cooling Load Estimation . You need to open or download this document to study this course.

Course Summary

The colder temperature allows primary air volumes to be reduced, compared to a conventional 55°F supply air design. While the conventional 55°F maintains an acceptable comfort conditions in a building, it does not necessarily offer the best annual energy performance or capital cost.

The cold air distribution system provide more cooling with lesser air. The benefits are that the AHU and duct sheet metal sizes are dramatically reduced, which in turn reduces first cost and operative cost of the HVAC system. Additional cost reductions are due to additional space created due to smaller equipments, reduced electrical requirements, reduced structural load requirements, and the reduction of the mechanical rooms.

The downside is that the colder air system can lead to the condensation on the duct surfaces. Dumping of cold air and balancing becomes difficult. These aspects require careful attention and are most often mitigated by the appropriate selection and installation of HVAC equipment.

Cold air systems demand more from the designer but when properly applied, the benefits are immense.

Quiz

Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.

DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.