Secondary Author(s)
Sherwin, John; Raustad, Richard; Shirey III, Don B.
Report Number
FSEC-PF-321-97
URL
http://publications.energyresearch.ucf.edu/wp-content/uploads/2018/06/FSEC-PF-321-97.pdf
Keywords
Buildings; HVAC, Evaporator coil; Air flow measurement; Residential air conditioning; Cooling capacity; Air conditioning performance; Duct sizing; Fan speed settings
Abstract
The performance of conventional split system residential air conditioners is highly dependent on adequate air flow across the evaporator coil. Sufficient air flow is necessary to achieve a proper balance between sensible and latent cooling capacity. Typical target air flow rates are approximately 350 - 450 cubic feet per minute per ton (581 - 747 L/S per kW) of cooling capacity. The authors have measured the air flow across the coil in 27 installations in Florida. Both flow hood and strip heat resistance methods were used to measure air flow with an established protocol. The installations measured ranged in capacity from 2 to 4 tons (7 - 14 kW). Measured air flows ranged from 130 to 510 cfm per ton (216 - 847 L/S per kW) with an mean of 320 cfm/ton (538 L/S per kW). Reasons for inadequate flows included undersized return ducts and grills, improper fan speed settings, fouled filters and cooling coils. High distribution system static pressures were due to long, circuitous runs and pinched or constricted ducts. Recommendations are made to improve current practice.
Date Published
6-1-1997
Identifiers
756
Subjects
Air conditioning; Air flow; Dwellings; Dwellings--Heating and ventilation--Equipment and supplies; Measurement
Local Subjects
Buildings - HVAC
Type
Text; Document
Collection
FSEC Energy Research Center® Collection
STARS Citation
Florida Solar Energy Center and Parker, Danny, "Impact of Evaporator Coil Air Flow in Residential Air Conditioning Systems" (1997). FSEC Energy Research Center®. 756.
https://stars.library.ucf.edu/fsec/756
Notes
Reference Publication: Parker, D., Sherwin, J., Raustad, R., Shirey, D., "Impact of Evaporator Coil Air Flow in Residential Air Conditioning Systems," Presented at the 1997 ASHRAE Annual Meeting, June 28July 2, Boston, MA