### Question
How is the "annual fuel utilization efficiency" defined?


### Answer
The term **annual fuel utilization efficiency** is defined in *42 U.S.C. § 6291* as follows -

> the efficiency descriptor for furnaces and boilers, determined using test procedures prescribed under section 6293 of this title and based on the assumption that all—


(A) weatherized warm air furnaces or boilers are located out-of-doors

#### Citation:
  - *42 U.S.C. § 6291*
  - Heading: **CHAPTER 76-AGE DISCRIMINATION IN FEDERALLY ASSISTED PROGRAMS > SUBCHAPTER III-IMPROVING ENERGY EFFICIENCY > Part A-Energy Conservation Program for Consumer Products Other Than Automobiles**

