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Title: Technology Solutions Case Study: Improving the Field Performance of Natural Gas Furnaces

The objective of this project is to examine the impact that common installation practices and age-induced equipment degradation may have on the installed performance of natural gas furnaces, as measured by steady-state efficiency and AFUE. PARR identified twelve furnaces of various ages and efficiencies that were operating in residential homes in the Des Moines Iowa metropolitan area and worked with a local HVAC contractor to retrieve them and test them for steady-state efficiency and AFUE in the lab. Prior to removal, system airflow, static pressure, equipment temperature rise, and flue loss measurements were recorded for each furnace. After removal from the field the furnaces were transported to the Gas Technology Institute (GTI) laboratory, where PARR conducted steady-state efficiency and AFUE testing. The test results show that steady-state efficiency in the field was 6.4% lower than that measured for the same furnaces under standard conditions in the lab, which included tuning the furnace input and air flow rate. Comparing AFUE measured under ASHRAE standard conditions with the label value shows no reduction in efficiency for the furnaces in this study over their 15 to 24 years of operation when tuned to standard conditions. Further analysis of the data showed no significantmore » correlation between efficiency change and the age or the rated efficiency of the furnace.« less
Publication Date:
OSTI Identifier:
Report Number(s):
Research Org:
Partnership for Advanced Residential Retrofit
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Building Technologies Office (EE-5B) (Building America)
Country of Publication:
United States
furnace; efficiency; AFUE; Iowa; field testing; laboratory testing; end of life; HVAC SAVE; high efficiency; furnace age; rated efficiency; ASHRAE Standard; induced draft; atmospheric; tracer gas; fan ajustment; firing rate adjustment; residential; residential buildings; PARR; Building America