BES708 - Air Systems Design

Outline info
Last revision date 2017-12-15 14:35:55.2
Last review date 2017-12-15 14:35:55.201

Subject Title
Air Systems Design

Subject Description
Students study the design, components and operating characteristics of air handling systems in order to heat and cool the air supply within a building in a safe, energy efficient and environmentally conscious manner.  Emphasis is on knowing the air systems' load capacity and ensuring system efficiency while maintaining a healthy environment for building inhabitants.

Credit Status
One elective credit in the Building Environmental Systems (BES) Class I Certificate Program

Learning Outcomes
Upon successful completion of this subject the student will be able to:

  • Determine fan sizes by applying knowledge of fan types, fan charts and diffuser charts.
  • Calculate air duct sizes and capacities using duct calculators.
  • Calculate ductwork and fitting resistances.
  • Make calculations for air handling systems using psychrometric charts.
  • Determine latent heat and sensible heat gain in a given situation.
  • Determine the supply of air required to resolve pressurization problems related to air leaked and/or exhausted.
  • Select diffusers for proper air distribution in a given situation.
  • Calculate the required flow capabilities of hydraulic components in gallons per minute (GPM) in a given situation.
  • Discuss methods of testing the components of an air system to achieve air balancing.
  • Determine proper pump sizes using pump charts 

Cheating and Plagiarism
Each student should be aware of the College's policy regarding Cheating and Plagiarism. Seneca's Academic Policy will be strictly enforced.

To support academic honesty at Seneca College, all work submitted by students may be reviewed for authenticity and originality, utilizing software tools and third party services. Please visit the Academic Honesty site on for further information regarding cheating and plagiarism policies and procedures.

All students and employees have the right to study and work in an environment that is free from discrimination and/or harassment. Language or activities that defeat this objective violate the College Policy on Discrimination/Harassment and shall not be tolerated. Information and assistance are available from the Student Conduct Office at

Accommodation for Students with Disabilities
The College will provide reasonable accommodation to students with disabilities in order to promote academic success. If you require accommodation, contact the Counselling and Disabilities Services Office at ext. 22900 to initiate the process for documenting, assessing and implementing your individual accommodation needs.

Class II desdignation recommended

Topic Outline

  • Types of fans and fan law
  • Fan charts and selection of fans from industrial practice
  • Pressures in fan and ductwork systems
  • Industrial practices to size ductwork and the application of "Trane Ductulator" to size ductwork
  • The equivalence of round and rectangular ductwork
  • System resistance including interpretation of elbow and other components losses
  • Fan systems including parallel fans, starter and motors consideration
  • Diffusers selection and layout with consideration of air throw, noise and air velocity
  • Properties of air determination by reading Psychrometric chart
  • Using the Psychrometric chart to interpret properties of air in air mixing
  • Ventilation requirement for different types of occupancies
  • Internal heat gain, cooling load of buildings
  • Stack effect in a building, building pressurization
  • Study of cooling system design:  cooling load evaluation with ventilation and humidity consideration, diffusers, ductwork layout and sizing of fan and coil selection
  • Air balance in ductwork and diffusers 

Mode of Instruction
Traditional Classroom
Lectures, discussions in the classroom, video 

Independent learning with tutor support.  Instructor will contact you by email. 

Prescribed Texts
BES708 Air System Design, Seneca College, ISBN/Sku #: 0-00011-708-B.  Available from the Seneca Bookstore.  

Correspondence students, your text fee is included and your text will be shipped to you.

Reference Material

Required Supplies

Promotion Policy

Grading Policy
A+ 90%  to  100%
A 80%  to  89%
B+ 75%  to  79%
B 70%  to  74%
C+ 65%  to  69%
C 60%  to  64%
D+ 55%  to  59%
D 50%  to  54%
F 0%    to  49% (Not a Pass)
EXC Excellent
SAT Satisfactory
UNSAT Unsatisfactory

For further information, see a copy of the Academic Policy, available online ( or at Seneca's Registrar's Offices.

Modes of Evaluation
Since this is a professional credit subject, marking standards reinforce professional practice by demanding legible, tidy work. Written assignments should be well organized and grammatically correct, with proper spelling and punctuation. Late assignments are penalized. Please obtain standards, dates and additional information from your instructor. 

While attendance is not a formal part of the evaluation process, absenteeism will almost guarantee your inability to achieve a satisfactory grade, as there is no formal provision for make-up tests or assignments you may miss. 

To attain a passing grade for the subject, a student must complete and obtain a passing grade on all combined assignments and tests during the term.  For further information on evaluation and academic standing, see a copy of the Academic Policy. They are available at Seneca Registration offices. 

Grading is based on the following marking scheme:

                              Classroom Delivery

Final Project 15%
Mid-Term Test 35%
Final Exam 50%

Mid-Term Exam 30%
Final Exam 50%
Assignment 20%

Approved by: Denis Gravelle