Heating, Ventilating, and Air-Conditioning: Recent Advances in Diagnostics and Controls to Improve Air-Handling System Performance

The performance of air-handling systems in buildings needs to be improved. Many of the deficiencies result from myths and lore and a lack of understanding about the non-linear physical principles embedded in the associated technologies. By incorporating these principles, a few important efforts related to diagnostics and controls have already begun to solve some of the problems. This paper illustrates three novel solutions: one rapidly assesses duct leakage, the second configures ad hoc duct-static-pressure reset strategies, and the third identifies useful intermittent ventilation strategies. By highlighting these efforts, this paper seeks to stimulate new research and technology developments that could further improve air-handling systems

Correlation between temperature satisfaction and unsolicited complaint rates in commercial buildings

Photo of a scene along the Colorado River during the Aaron Belnap Ross river trip through the Grand Canyon in the spring of 1968

Worker performance and ventilation: Analyses of individual data for call-center workers

We investigated the relationship between ventilation rates and work performance in a call center. We randomized the ventilation controls and measured ventilation rate, differential carbon dioxide ({Delta}CO{sub 2}) concentration, temperature, humidity, occupant density, degree of under-staffing, shift length, time of day, and time required to complete two different work performance tasks (talk and wrap-up). {Delta}CO{sub 2} concentrations ranged from 13 to 611 ppm. We used multi-variable regression to model the association between the predictors and the responses. We found that agents performed talk tasks fastest when the ventilation rate was highest, but that the relationship between talk performance and ventilation was not monotone. We did not find a statistically significant association between wrap-up performance and ventilation. At high temperatures agents were slower at both the talk and wrap-up tasks. Agents were slower at wrap-up during long shifts and when the call center was under-staffed