Estimation of the mean time between failures (hereinafter termed MTBF) for random failure is a well-known part of equipment engineering, but no discussion of MTBF presently exists in connection with building equipment. Close examination of the interval estimation of MTBF is indispensable in establishing maintenance periods for building automation and other systems.

In this study, an investigation of MTBF estimation for random failure is made using field data of building equipment operations, and a comparison of results is conducted by applying two methods of interval estimation. The study touches upon the relationship of the results achieved by the Bayesian approach with the assessed values of practical operations. We employ simulation of a maximum-likelihood method with the Bayesian method in estimating the failure rate and then analyze it by using the data of building equipment and devices for a period of random failure. These results suggest the most suitable and practical way of MTBF estimation for actual maintenance sites.

Units: Dual