PART-001: Concept of Heating Ventilation and Air-Conditioning (HVAC) for beginners

I am starting a series of blogs for explaining difficult HAVC (Heating ventilation and air-conditioning) concept into simple language. Theoretical knowledge we all can get from books. But for practical knowledge we have to work hard in our field. I have 12 years and counting experience in HVAC industry. Thus, I will focus more on practical aspect of HVAC. If you find it interesting please like and share the blog to keep me motivated. We all need motivation. Without constant motivation we lose interest and stop doing whatever we started.

 After my job and daily work very little time is left for relaxing and leisure which I utilize in writing blogs. My primary purpose of writing blogs is to motivate peoples and share my ideas. Also I want to make more connections with the world which will help me to start my social organization to help needy peoples.

I hope you all will support me in this cause and we succeed together. My focus is on HTS-Humanity, Technology and Sustainability. Thanks for your support and hope I will get even more support in future. All type of questions based on the current topic are welcome.

Today, I want to discuss about aspect ratio in ducting. What is it and how is it so important?


Aspect ratio is very simple term. It is the ratio of two sides of duct, i.e. height: width. We consider 1:4 as acceptable aspect ratios as per standards. It is always better to have lower aspect ratio up to 1:1 .That means square duct. As aspect ratio increases, friction to air flow increases and thus cost of fan too increases. Similarly, cost of material also increases with increase in aspect ratio. Because thickness (gauge) of GI sheet (or any other duct material) used for duct-work depends on the size of duct. If you increase one side of duct, thickness of sheet will increase after specified size. As we move from square to rectangle, surface area increases. Increase in surface area increases duct heat loss. Furthermore, insulation material is increases because of increase in surface area.

Though, aspect ratio looks like very trivial term, but cost wise it plays very important role. Therefore, always keep aspect ratio in range of 1:1 to 1:2 and maximum up to 1:4 which is acceptable in case when there is no enough space to install the duct. In all such conditions you are supposed to re-calculate the ESP of fan before making decision to change the size.


Written by Peace&Humanity

I am a simple person from India. I want to help poor and needy people. My aim is to start an organisation to promote sustainability and to make everyone's life better.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s