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DOE OSTI · 3364909

Hot Water Recirculation Systems: Designing for Success [Slides]

Cummings, Meredith [National Laboratory of the Rockies (NLR), Golden, CO (United States)]·Dennehy, Conor [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000330950763)·Boetzel, Alex [Earth Advantage, Portland, OR (United States)]·Strongin, Dana [National Laboratory of the Rockies (NLR), Golden, CO (United States)]·Cook, Deanna [National Laboratory of the Rockies (NLR), Golden, CO (United States)]
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Abstract

This presentation will focus on on-demand hot water recirculation systems and how they contribute to energy and water conservation in residential buildings. This work illustrates best practices for designing, installing, and operating these systems, drawing from research and field testing to provide practical recommendations. The ultimate goal is to reduce wait times for hot water, comply with current energy codes, and lower both energy use and greenhouse gas emissions, while improving user satisfaction. In the upcoming slides, we'll dive into case studies and explore the latest technological advancements that help achieve these objectives.

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32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATIONcontrol timerdomestic hot wateron-demand hot waterrecirculationtankless water heaterswater temperature

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Cummings, Meredith [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Dennehy, Conor [National Laboratory of the Rockies (NLR), Golden, CO (United States)] (ORCID:0000000330950763), Boetzel, Alex [Earth Advantage, Portland, OR (United States)], Strongin, Dana [National Laboratory of the Rockies (NLR), Golden, CO (United States)], Cook, Deanna [National Laboratory of the Rockies (NLR), Golden, CO (United States)]. 2026-05-18. Hot Water Recirculation Systems: Designing for Success [Slides]. https://doi.org/10.2172/3364909

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