Reliability Analysis and Cost-Effectiveness of Large Commercial HVAC Systems with Regenerating Points and Semi-Markov Processes

Résumé

Global change in climatic conditions has led to increase in global temperatures, and hence the need for heating, ventilation, and air-conditioning (HVAC) systems has increased significantly. These systems play a vital role in regulating indoor environments and ensuring comfortable temperatures in both residential and commercial spaces. This paper delves into the intricate analysis of large commercial HVAC systems comprising two similar cooling or heating units and a dissimilar unit dedicated to ventilation. These systems play a pivotal role in maintaining comfortable climate conditions, ensuring occupant comfort and operational efficiency. The study begins with three functioning units, where any two units are sufficient to sustain system operation. One crucial aspect addressed is the warranty coverage of these units, guaranteeing that any malfunctioning unit undergoes restoration at no additional cost within the stipulated warranty period. The restoration process is assumed to be flawless, conducted by a proficient service provider, with restoration times following an exponential distribution. Employing advanced methodologies such as the regenerating point technique and semi-Markov processes, this paper formulates equations to evaluate key reliability metrics and the profit function. These metrics encompass constant failure rates and consider the duration of the warranty periods, providing valuable insights into system reliability and cost-effectiveness.