Modulating Furnace and Zoned Heating System Development. Final Report, July 1987-December 1989

摘要

The report describes an experimental modulating furnace and a zoned warm air heating system for use in residences. The system was installed and tested at the National Association of Home Builders' (NAHB) SMART HOUSE in Bowie, Maryland. The key features of this system include: (1) continuous modulation of firing rate and supply air over a wide range, (2) closed-loop control to maintain a desired supply air flow under varying system resistances, (3) continuous modulation of combustion air to maintain efficiency, (4) a proportional-integral control algorithm operating on measured temperatures and set points in each zone to set the furnace firing rate, (5) low-cost on/off dampers to direct air flow to those zones calling for heat, and (6) a single microprocessor-based controller that integrates all aspects of the system.