Hvac Duct Design Example
Let s say we have a section of ductwork that needs to move 400 cfm.
Hvac duct design example. In this video we ll be learning how to size and design a ductwork for efficiency. Our friction rate is 0 073 iwc 100. All information provided in this document is to be used as a guideline only. Consequently the total pressure or total energy of air flowing in a duct system is generally equal to the sum of the static pressure and the velocity pressure.
As an equation this is written. On the friction loss air quantity part of the dial we line up 0 073 with 400 cfm as seen below. 8 6 perimeter loop system. Scroll to the bottom to watch the free youtube video tutorial.
Duct system design page 1 5 energy is due to elevation above a reference datum and is often negligible in hvac duct design systems. How to design a duct system. 7 1 fan selection example. How to design a duct system.
We ll include a full worked example as well as using cfd simulations to optimise the performance and efficiency using simscale. 7 3 fan system effect. Ductwork design considerations 33 11 1 duct frictional resistance 33 11 2 duct equivalent length 35 11 3 ductwork system effect 35 11 4 installation issues 37 11 5 ductwork insulation 38 11 6 ductwork air leakage 39 11 7 testing methods and equipment 40 11 8 ductwork sealing 41. 8 3 reducing trunk system.
Above and below are examples of simple hvac duct systems. Includes a full worked example as well as usin. 8 1 extended plenum systems. 8 2 reducing plenum system.
8 4 spider system 8 5 radial system. Design cfm 4 cfm 6 cfm 8 cfm 10 cfm 12 60 6x4 60 4x6 90 4x8 120 4x10 150 4x12 90 8x4 110 6x6 160 6x8 215 6x10 270 6x12 120 10x4 160 8x6 230 8x8 310 8x10 400 8x12 150 12x4 215 10x6 310 10x8 430 10x10 550 10x12 180 14x4 270 12x6 400 12x8 550 12x10 680 12x12 210 16x4 320 14x6 490 14x8 670 14x10 800 14x12 240 18x4 375 16x6 580 16x8 800 16x10 950 16x12 270 20x4 430 18x6 670 18x8 930 18x10 1100. Understanding basic residential ductwork design please note. The diagram above illustrates the fact that the air handler may be centrally located preferred or located elsewhere dependent upon the configuration of your home.
7 2 balancing air. 8 7 rules of duct design acca manual d residential duct systems 9 0. I ll follow that up with articles on the process we use in designing duct systems including available static pressure equivalent length and choosing fittings. Duct sizing for the two examples would certainly be very different.
The purpose of residential ductwork design is to properly distribute the airflow produced by your heating cooling system to your house. Today i ll start with what you do in the hvac design process before you get to the duct design phase manual d as well as the physics of air flow when it s constrained by ducts.