Interpretation #7560
Published August 01, 2015
Original Request
- Code Version
- 2014
- Code
- BUILDING
- Code Description
- Chapter
- Section
- R403.2.4
- Topic
- Replacing an AHU in the attic
Question
Is it the intent of section R403.2.4 that new replacement air handlers in attics to be in compliance with section 405 and the conditions that are listed, or can an air handler in the attic be replaced without compliance with section R405 as long as the listed items are followed?
Answer Published 08/01/2015 at 2:55 PM
An existing attic installed air handler can be replaced in
exactly the same location and the ONLY requirement that must
be met is that matched equipment is required as specified in
R101.4.7(2).
exactly the same location and the ONLY requirement that must
be met is that matched equipment is required as specified in
R101.4.7(2).
Commentary
The section is saying air handling units may be installed in
attics for new construction only when the performance path
of Section 405 is used. When installing in attics, all four
conditions of R403.2.4 must be met. The conditions are a
Florida specific amendment which was the result of an
agreement between the Florida Building Commission and the
Florida Home Builders Association to resolve a rule
challenge in the first edition of the code.
The first edition prohibited the installation of air
handlers in attics outright. Not sure where the requirement
that the unit be installed using the performance method
originated, but it first showed up in the 2010 Edition.