Control Algorithms for Building Management and Control Systems -- Hot Deck/Cold Deck/Supply Air Reset, Day/Night Setback, Ventilation Purging, and Hot and Chilled Water Reset

摘要

Software is an important component of building management and control systems (BMCS). This report describes concepts, algorithms, and software used in BMCS components developed in the NBS building systems and controls laboratory. The basic concepts, considerations and general algorithms for hot deck/cold deck supply air setpoint reset, day/night thermostat and ventilation setback, ventilation purging, and hot/chilled water supply setpoint reset are presented. Reset is the changing of a setpoint on a Heating, Ventilating and Air Conditioning (HVAC) system controlled by a feedback controller to match the system output to the system load. Setback is the changing of HVAC system operation to reduce energy use during unoccupied periods. Purging is the use of outdoor air during unoccupied periods to reduce mechanical conditioning requirements. Specific implementations of the algorithms in software on an actual BMCS are presented as examples.