A unit heater needs an ordinary threaded union that is not a listed CSST fitting. Under unamended 2021 IFGC Section 404.5 and the definition of concealed location, which proposed location avoids the concealed-fitting restriction?
- AInside a sealed wall chase that can be reached only by cutting permanent drywall
- BAbove a fixed plaster ceiling that must be broken for access
- CInside a closed floor assembly requiring removal of permanent finish for access
- In exposed, accessible piping beside the heater on the appliance side of its shutoff valve
Where to look it up
https://www.ncosfm.gov/b-2-2024-ncfgc/open
Why D is correct
Section 404.5 limits fitting types in concealed locations; an ordinary threaded union is not in that list. The definition concerns whether access requires damage to permanent structure or finish. Spaces behind readily removable panels or doors are not concealed merely because they are out of sight. Thus a removable suspended ceiling or an accessible crawl space cannot automatically be rejected as concealed, as the original explanation did. The exposed appliance location avoids the stated restriction; other appliance, valve, listing and installation requirements still apply. See PDF pp.14 and 83. Source: 2021 IFGC model text reproduced in OSFM comparison, https://www.ncosfm.gov/b-2-2024-ncfgc/open