Ignition Sources for Atmospheric Gas Burners

Robert P. Jackson, P.E.

Course Outline

This thee hour course is intended to provide a basic but in-depth overview of ignitions systems used for domestic and commercial atmospheric gas burners.  We will highlight the differences between the nine systems available in today’s marketplace and how the application of each system can mean the difference between success and failure of a burner system.  We will provide a check list that will aid trouble-shooting ignition problems encountered on a daily basis in “real-world” applications.   The first part of the course is intended to provide an overview for the fundamentals of gaseous fuels.  The major divisions for the course are as follows:

• REFERENCES—All references used in the formation of tables, charts, etc are given at the very beginning of the course.
• FUNDAMENTALS OF GASEOUS FUELS—In order to really understand the operation of ignition sources for gas-fired burners, it is imperative that the very basics of combustion be understood.  Understanding the fundamentals relative to the nature of combustible gases certainly will aid efforts in selecting and specifying an ignition source.
• BURNER CHARACTERISTICS-The most critical relationships involving burner components and operation are given as an overview.
• IGNITION SYSTEMS—We present the ignition types used in the domestic and commercial marketplace today.
• TROUBLE-SHOOTING IGNITION SYSTEMS—An in-depth discussion of what can go wrong and how to fix it is presented for each ignition system type.  We detail, using a checklist, how to go about “ticking off” items that can cause significant problems to any one given ignition system.
  

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

Learning Objective

Upon completion of this course, the student will:

• Fully understand the nine types of ignition methods that might be used for initiating combustion of gaseous fuels;
• Understand the eight ignition sources used for atmospheric gas-fired burner systems;
• Know the benefits of using one ignition type over another and why choosing the proper type will save hours of maintenance and operating down-time;
• Know the basic rules governing use of the “best ignition type” for any one given burner application and input;
• Be able to trouble-shoot issues with ignition types and determine the necessary and proper “fix”;
• Know the basic components for 1.) standing pilot systems, 2.) spark ignition systems, 3.) re-ignition systems, 4.) FFD systems,5.) piezoelectric systems and 6.) hot surface ignition systems;
• Be able to recognize “ideal burner characteristics”. ( This is given in the overview for “good combustion”);
• Understanding why proper “grounding” is critical to certain types of ignition systems;
• Be able to recognize a burner operating improperly and have solutions for a “fix”. ( This is given in the overview for “bad combustion”);
• Fully understand the difference between natural gas, LP gas and manufactured gas and the relevance of those fuels in today’s marketplace;
• Be given “gas facts” charts that will indicate the most important characteristics of those gases used, over the world, for fuels in today’s domestic and commercial markets;
• Understand the importance of orifice design and the “K” factor defining that design;
• Know and understand the difference between a fixed orifice and an adjustable orifice;
• Understand the equation for calculating the flow rate through a burner orifice;
• Be able to calculate and select the proper orifice diameter, depth and spacing so that good combustion and a desirable flame appearance may be had;
• Learn the differences between an FFD system and a re-ignition system;
• Understand relationships involving the interchangeability of gasses; i.e. natural to propane, natural to manufactured and be given the names of the most-used mathematical models for determining interchangeability;
• Have an understanding of the appropriate ANSI test gases and ANSI test pressures for domestic and commercial burner products;
• Understand why altitude can have a dramatic effect upon a gas-fired system;
• Have a complete understanding of the issues that are deemed most critical to burner performance and the most critical relationships between burner components;
• Know why spark electrode placement is so important to the proper ignition of a burner;
• Understand why a spark ignition system is generally preferable to a standing pilot system;
• Understand why “crimp heights” can be so critical to a several ignition systems; and
• Be able to calculate the “Wobbe Index” for any gas.

Intended Audience

This course is designed to be a companion course to “Fundamentals of Gas Combustion”, M273 and “Design of Atmospheric Gas Burners, M367.   All three courses and structured to stand alone and one does not depend upon the other for understanding.  Neither “Fundamentals” nor “Design” are prerequisites although both would give a better understanding of basic principals relative to gas-fired products.  “Ignition Systems for Gas Burners” represents the third in a trilogy of courses relative to atmospheric gas-fired systems.  The following professional disciplines will benefit from completion of this three (3) hour course:

• Engineers interested in obtaining a better understanding of the various methods by which atmospheric gas burners are ignited and the basic design principals upon which successful operation depends.
• Engineering managers responsible for personnel dealing with gas burners and gas-fired products.
• Laboratory technicians involved with testing products using gas burners.
• Laboratory managers.
• Service personnel required to diagnose problems with products incorporating gas burners.
• Quality control specialists who wish to broaden their understanding of ignition sources.
• Sales and marketing personnel who deal with products incorporating gas burners. (NOTE:  This is a technical course using one mathematical formula to describe the calculation for computing flow rate through a burner orifice.  Any person that can manipulate a calculator to determine the square root of a factor can do the math needed. )  
• Reliability specialists interesting in obtaining a better understanding of gas burner design and operation.
• Any individual interested in what makes a burner ignition system “tick”.
  

Benefit to Attendees

This course is designed to provide a thorough survey of ignition systems available for atmospheric gas burners.  We will look at design principals governing system use and operation and how the ignition systems are applied to burner “hardware”.   Upon completion of this course, an individual will have a much better appreciation for the methodology of system design and will have a complete understanding of how to trouble-shoot any specific ignition problem.   We emphasize how to make the proper selection relative to burner type and frequency of burner use.  There is a very complete overview of the fundamentals of gas combustion and basic “gas facts” governing the chemical characteristics of natural gas, propane, butane and manufactured gas.   This overview is presented to provide a better understanding of how gas type can effect the ignition and operation of any burner.  Ignition systems, and the selection thereof, can complement or detract from burner ignition and operation.  The subject is absolutely critical to proper combustion of atmospheric gas burners. 

Course Introduction

On June 8, 2010 this author was honored by being asked to present a paper on The Fundamentals of Ignition Systems for Atmospheric Gas-Fired Burners.  The forum was the American Society of Gas Engineers; their annual meeting in Las Vegas.   The required format for the presentation was Microsoft Power Point.   I was encouraged by the fine people at PDH to develop this into a presentation that represents the third in a series of courses designed to increase the understanding of interested individuals relative to combustion of fuels, burner design and ignition systems for burners.   The course is structured around the following two main subjects:       

• IGNITION SYSTEM TYPES AND SELECTION
• TROUBLE-SHOOTING IGNITION SYSTEMS

It is a three (3) hour survey course that includes a brief overview of the fundamentals of gaseous fuels and the important relationships between burner components.  You do not have to have, as prerequisite, either of the two previous courses.   “Ignition Systems” is a stand-alone course that will broaden your understanding of gas combustion in general, certainly relative to ignition systems.   Our purpose is to impart enough information to an engineer, sales representative, engineering manager, etc, so that proper selection of a system may be accomplished.  This, of course, is done by discussing ignition types and selection with the proper suppliers.  We just wish to lessen the “intimation factor” of a subject that can be quite complex.

Course Content

The course content is in a PDF file:

Ignition Sources for Atmospheric Gas Burners

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Course Summary

This course is intended to be the third in a trilogy of courses designed to inform interested individuals about the ignition of gaseous fuels.  The first two courses, “Fundamentals of Gas Combustion” ( M273 ) and “Design of Atmospheric Gas Burners” ( M367 ) have been published previously through PDHonline.com.  In the first two courses, we discuss the fundamentals of gas combustion and the design of gas burners.  In those courses, we touched hastily on ignition devices available to ignite the gas-air mixture produced during the gas injection process.  “Ignition Sources for Atmospheric Gas Burners” takes the process considerably further by providing much greater detail.  It is a three hour survey course designed to explain ignition types and methods of trouble-shooting those ignition types.  Explanations are in-depth and designed to provide the reader with definite “talking points” so that proper specifications and problem solutions may be developed.   Our purpose is to provide enough knowledge to enable conversations with sales representatives and engineers that will not be intimidating and will result in a more productive exchange of ideas and information.

Quiz

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

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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.

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