Arkansas HVACR NewsMagazine January 2020

Obviously, this condition was created by failure to properly seal. Perhaps it was a bad day for the installer, a pattern of negligence, or ignorance of the jobs importance. Whatever, it contributed to the overall problem. 5. (#1 & #3 investigator) Conditioned Air Supplied to Attic According to the engineer, “two 4” supply ducts and 6” return ducts in the attic were added per city’s request.” He and Healthy Homes’, Bobby Park, recommended that the attic supply and return air be sealed / closed. Bobby Park said, “…supply air vents…should NOT be supplying conditioned air to the attic space.” Potential Problem: With a system being supplied “fresh”, hot, humid air and the fan in the on position, investigators #1 and #3 are probably right. The system was pumping unconditioned outside air into the attic anytime the unit was not conditioning. In all likelihood, there was insufficient air being supplied to the attic to properly circulate and dehumidify the air had the fan not been in the on position. At a friction rate of 0.1, two 4” supplies would have only provided 78cfm. I don’t have the exact numbers on the volume of the attic so I can’t say unequivocally that 78cfm was insufficient. I can say that this is a large attic. The question could be, “Why did the city request that the supply air be added to the attic?” I can only speculate because the city inspector of record has retired; but, let me

interject. That inspector has a reputation of being tough; meaning, he wanted the jobs to be done right. I have no doubt that he thought he was doing the right thing---especially since the Health Department at the time was recommending that this be a potential solution to high humidity in encapsulated attics. By way of totally transparency, I included that method as a potential methodology in the January 2019 issue of the NewsMagazine. Also, let me note that in an industry meeting, Healthy Homes personnel said the introduction of conditioned air in an encapsulated space was not necessary but also interjected that it would be OK. It should also be noted that the conversation was regarding residential applications and there was no thought of fresh air being introduced into the system or that the encapsulated attic would not be perfectly sealed thus allowing hot, humid air to enter. Also, there was no thought of the fan being in the “on” position. 6. (#1, #2, and #3 investigators) Duct was not properly sealed. All three investigators found the duct to be improperly sealed and recommended “all the insulation gaps be corrected and taped secure.” Potential Problem: It was stated and pictures provided in the first article that the duct was not properly sealed and this was reiterated by all three investigators referenced in this article. Here there is no question as to who was at fault. The duct installers sealed some