Jump to content

Featured Articles

Check out the latest featured articles.

File Library

Check out the latest downloads available in the File Library.

New Article

Product Viscosity vs. Shear

Featured File

Vertical Tank Selection

New Blog Entry

Low Flow in Pipes- posted in Ankur's blog


Air Flow To Natural Draft Fired Heaters During Startup

2 replies to this topic
Share this topic:
| More

#1 Venkat1989


    Veteran Member

  • Members
  • 42 posts

Posted 01 April 2019 - 07:56 PM

Hello everyone,

I would like to know, in natural draft fired heaters, there is no external fan to provide air required for combustion, the only way to get air is to draw it from atmosphere with the help of draft produced in the fired heater through burner air registers.

However, I would be grateful if someone helps me to understand, how air is entering the natural draft fired heater during startup when there is no draft, as there is no temperature difference between atmospheric air and gas medium in the stack??

#2 Pilesar


    Gold Member

  • Members
  • 571 posts

Posted 02 April 2019 - 04:36 AM

Before the fired heater is lit, there is already air at the burner due to atmospheric pressure phenomenon. After a small fire is lit, the hot combustion products are lighter and rise, More atmospheric air is pushed to the flame as the combustion products rise. This air movement soon forms a general flow pattern and gets stronger as more fuel is added. The key is to start with a small fire to heat the unit and gradually get the desired air movement started.

#3 Art Montemayor

Art Montemayor

    Gold Member

  • Admin
  • 5,721 posts

Posted 02 April 2019 - 12:07 PM



Please read the following guidelines posted on the Student Forum for your benefit:


"1. Please be sure to post to the correct forums. Students should post in the student forum, while professionals should use the Industrial Professional and other forums.

2. Please do not post the same question in multiple forums."


Please follow these instructions.  Our Forums are organized to keep and have experienced knowledge available to our members in an efficient way.  What you are doing by posting the same query in different Forums is creating chaos and disorganization.  Please stop this practice.  You are causing more work for me and others trying to have and keep an organized website for all members.


I am deleting your first post in the Student Forum and moving this post where it belongs - the Student Forum.

Similar Topics