### Question
What does warm air furnace mean?


### Answer
**Warm air furnace** has the following meaning in *42 U.S.C. § 6311*:

> a self-contained oil- or gas-fired furnace designed to supply heated air through ducts to spaces that require it and includes combination warm air furnace/electric air conditioning units but does not include unit heaters and duct furnaces

#### Citation:
  - *42 U.S.C. § 6311*
  - Heading: **CHAPTER 77-ENERGY CONSERVATION > SUBCHAPTER III-IMPROVING ENERGY EFFICIENCY > Part A&ndash;1-Certain Industrial Equipment**

