Full Description

Low evaporator airflow is one of the common faults forrooftop units. It can be caused by dirty filters, evaporatorfouling, or loose belts. Low airflow could result in frozenevaporator coils, reduced cooling capacity, and indoorcomfort issues. Accordingly, more fan power is consumed aslonger operating time is required. With the widespread use ofvariable-frequency drives (VFDs) on rooftop units (RTUs),low evaporator airflow can be potentially detected by monitoringthe fan-power variation. In this paper the principle offan-power-based detection is introduced first. Then, thedetection algorithm is proposed, including development ofthe baseline and comparison of operational data with thebaseline. Finally, the conducted field test is discussed, verifyingthe proposed methods. The test results indicate that thefan-power-based method can effectively detect low evaporatorairflow for rooftop units.

Citation: 2016 Annual Conference, St. Louis, MO, Transactions 2016, Vol 122 pt. 2

Product Details

Published: 2016 Number of Pages: 7Units of Measure:DualFile Size: 1 file , 2.1 MB Product Code(s): D-ST-16-024