This paper is based on findings resulting from ASHRAE Research Project RP-1455.

This paper describes two of the unique elements of the advanced control sequences developed for ASHRAE Research Project 1455 on automatic fault detection and diagnostics (AFDD) and hierarchical alarm suppression. AFDD is a method used to identify fault conditions and provide possible diagnoses. Hierarchical fault suppression is a method based on hierarchical structure used to reduce the incidence of the nuisance alarms. This paper is written by the members of the research team and is part of the deliverables for this research project. AFDD and hierarchic alarm suppression will further enhance the ability of direct control (DDC) systems to make intelligent alarm distribution and managment decisions.