TIA UMC 005-15 would amend Section 603.4.1 of the 2015 UMC to include language permitting the use of flexible air ducts as an elbow at a terminal device.

The journey to 15 million TR6 valves began in 2003, when the minimum seasonal energy efficiency ratio rating for residential air-conditioning systems in the U.S. was SEER 10. 

AHRI and its industry partners have advocated for a broader interpretation of what constitutes an "error" warranting reconsideration of the substance of a pre-published rule.