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Title: Final Report: Cooling Seasonal Energy and Peak Demand Impacts of Improved Duct Insulation on Fixed-Capacity (SEER 13) and Variable-Capacity (SEER 22) Heat Pumps

Technical Report ·
DOI:https://doi.org/10.2172/1324529· OSTI ID:1324529
 [1];  [1];  [1]
  1. Building America Partnership for Improved Residential Construction, Cocoa, FL (United States); Florida Solar Energy Center (FSEC), Cocoa, FL (United States)

A new generation of full variable-capacity, central, ducted air-conditioning (AC) and heat pump units has come on the market, and they promise to deliver increased cooling (and heating) efficiency. They are controlled differently than standard single-capacity (fixed-capacity) systems. Instead of cycling on at full capacity and then cycling off when the thermostat is satisfied, they can vary their capacity over a wide range (approximately 40% to 118% of nominal full capacity), thus staying “on” for up to twice as many hours per day compared to fixed-capacity systems of the same nominal capacity. The heating and cooling capacity is varied by adjusting the indoor fan air flow rate, compressor, and refrigerant flow rate as well as the outdoor unit fan air flow rate. Note that two-stage AC or heat pump systems were not evaluated in this research effort. The term dwell is used to refer to the amount of time distributed air spends inside ductwork during space-conditioning cycles. Longer run times mean greater dwell time and therefore greater exposure to conductive gains and losses.

Research Organization:
Building America Partnership for Improved Residential Construction, Cocoa, FL (United States); Florida Solar Energy Center (FSEC), Cocoa, FL (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Building Technologies Office (EE-5B). Building America Program
DOE Contract Number:
AC36-08GO28308; KNDJ-0-40339-02
OSTI ID:
1324529
Report Number(s):
NREL/SR-5500-64695; DOE/GO-102016-4720
Country of Publication:
United States
Language:
English