Analysis of Automated Fault Detection and Diagnostics Records as an Indicator of HVAC Fault Prevalence: Methodology and Preliminary Results

Faults in commercial buildings can cause energy waste and other performance problems such as reduced occupant comfort, reduced equipment longevity, and increased noise. However, it is currently unknown how commonly faults occur in different equipment types. This paper describes a method to estimate the prevalence of faults in air handling units, air terminal units, and rooftop units and the use of three metrics for summarizing results. This method was developed by the authors as part of a study which includes data from several automated fault detection and diagnostics (AFDD) data providers, providing a large sample with a wide range of building types, geographical locations, and equipment types. This dataset includes fault diagnoses from thousands of buildings throughout the United States, as well as anonymized metadata describing the building and equipment characteristics. The number of fault records is on the order of 106. We describe here how the data from different data providers can be processed and unified using a common taxonomy, and illustrate three metrics that can provide insights using this type of data. The methods developed for this study are illustrated here with preliminary data. This work supports a multi-year, multi-institutional project that will provide insight into the drivers of fault prevalence; for example, whether prevalence is correlated with characteristics like building type, building size, and geographical location (including related factors like local climate and utility rates). We discuss some of the challenges of harmonizing disparate outputs from multiple AFDD providers, the usefulness of applying a unifying fault taxonomy, and provide preliminary figures that illustrate three fault prevalence metrics

Advanced Energy Retrofit Guide Retail Buildings

The Advanced Energy Retrofit Guide for Retail Buildings is a component of the Department of Energy’s Advanced Energy Retrofit Guides for Existing Buildings series. The aim of the guides is to facilitate a rapid escalation in the number of energy efficiency projects in existing buildings and to enhance the quality and depth of those projects. By presenting general project planning guidance as well as financial payback metrics for the most common energy efficiency measures, these guides provide a practical roadmap to effectively planning and implementing performance improvements for existing buildings

The twilight of the Liberal Social Contract? On the Reception of Rawlsian Political Liberalism

This chapter discusses the Rawlsian project of public reason, or public justification-based 'political' liberalism, and its reception. After a brief philosophical rather than philological reconstruction of the project, the chapter revolves around a distinction between idealist and realist responses to it. Focusing on political liberalism’s critical reception illuminates an overarching question: was Rawls’s revival of a contractualist approach to liberal legitimacy a fruitful move for liberalism and/or the social contract tradition? The last section contains a largely negative answer to that question. Nonetheless the chapter's conclusion shows that the research programme of political liberalism provided and continues to provide illuminating insights into the limitations of liberal contractualism, especially under conditions of persistent and radical diversity. The programme is, however, less receptive to challenges to do with the relative decline of the power of modern states

Constitutivism

A brief explanation and overview of constitutivism

Philosophy of action

The philosophical study of human action begins with Plato and Aristotle. Their influence in late antiquity and the Middle Ages yielded sophisticated theories of action and motivation, notably in the works of Augustine and Aquinas.1 But the ideas that were dominant in 1945 have their roots in the early modern period, when advances in physics and mathematics reshaped philosophy