The problem:Replacing an existing gas furnace with a new, more efficient furnace.
The apprentice:Allen Charles Edwards (ACE) – First-year mechanic.
The technician:N. Arthur Thomas Egan (NATE) – 15-year veteran.

Nate and Ace have been working to replace an older gas furnace with a more efficient furnace. They have determined that they will use 30 ft of 5-in. Type B venting system for the new Category I appliance (although they have calculated that they technically need 26.5 ft). Ace is perplexed by the two codes that Nate used in determining the length of material needed.

NATE: “Ace, I think we need to discuss a few differences in code interpretations.”

ACE: “Why, aren’t all the codes the same?”

NATE: “Yes and no. The main code focus is the minimum safe requirements for the installation and maintenance of an appliance.”

ACE: “Well, which one do we have to use?”

NATE: “In this particular area, we use the current edition of the National Fuel Gas Code or the International Fuel Gas Code. However, there are other areas that use different codes and different editions of the codes. The most important thing to understand is that you must talk to the local code enforcement department to make sure you follow the proper code.”

NATE: “Can you name some of the other codes that might be applicable?”

a) Uniform Mechanical Code
b) International Mechanical Code
c) National Fuel Gas Code
d) International Fuel Gas Code
e) All of the above

ACE: “Well, since we follow the National Fuel Gas Code or the International Fuel Code, then we can just ignore the others, right?”

a) Yes
b) No

ACE: “I noticed that they don’t mention an inspector specifically in the codes. Which one of the following could be in charge?”

a) Administrative authority
b) Code official
c) Building Department
d) Department of Mechanical Inspection
e) All of the above

ACE: “Can you let me know what other sections might apply in other areas that we work in so I can look up the information on the venting systems?”

NATE: “Sure. You can look in …”

a) National Fuel Gas Code 7.6.2
b) International Mechanical Code 801.1
c) Uniform Mechanical Code 806.4
d) International Fuel Gas Code 503.6.6
e) All of the above

NATE: “Ace, the most important thing to remember is to maintain a good relationship with the inspectors and stay current with whatever code is being used in the area.”

Answers: 1) e; 2) b; 3) e; 4) e

Author’s Note:
Many of you have commented to me regarding the articles that appear in The News.

I must explain that the questions that appear in these articles are not on the NATE Exams. The article questions and dialogue are my own creation and mine alone. The NATE Technical Committee does not review the article content. Only the committee has the final decision-making power for the use of a question on the tests.

The interpretations of code questions that appear in the articles come from my experience with the “authority having jurisdiction.” Different jurisdictions use different codes with different inspector views. The particular location of a job will dictate which code is used.

Please accept my apology for any discrepancies that may appear. The input I receive from readers is a valuable resource. Please feel free to continue commenting.

Patrick L. Murphy
Director of Technical Development

Murphy is director of technical development, North American Technician Excellence. If you have any further questions or comments on this Fundamentals quiz, contact Murphy at (e-mail).

Publication date: 04/29/2002