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Title: Building America Case Study: Balancing Hydronic Systems in Multifamily Buildings, Chicago, Illinois (Fact Sheet). Technology Solutions for New and Existing Homes, Energy Efficiency & Renewable Energy (EERE).
Pages/Volumes: 2 pp.
Publication Year: 2014
Notes: Work performed by the Partnership for Advanced Residential Retrofit (PARR).
Document Type: Factsheet, Flyer, Pamphlet
NTIS/GPO Number: 1158444
Abstract: In multifamily hydronic systems, temperature imbalance may be caused by undersized piping, improperly adjusted balancing valves, inefficient water temperature and flow levels, and owner/occupant interaction with the boilers, distribution and controls. The effects of imbalance include tenant discomfort, higher energy use intensity and inefficient building operation. This paper explores cost-effective distribution upgrades and balancing measures in multifamily hydronic systems, providing a resource to contractors, auditors, and building owners on best practices to improve tenant comfort and lower operating costs. The research was conducted by The Partnership for Advanced Residential Retrofit (PARR) in conjunction with Elevate Energy. The team surveyed existing knowledge on cost-effective retrofits for optimizing distribution in typical multifamily hydronic systems, with the aim of identifying common situations and solutions, and then conducted case studies on two Chicago area buildings with known balancing issues in order to quantify the extent of temperature imbalance. At one of these buildings a booster pump was installed on a loop to an underheated wing of the building. This study found that unit temperature in a multifamily hydronic building can vary as much as 61 degrees F, particularly if windows are opened or tenants use intermittent supplemental heating sources like oven ranges. Average temperature spread at the building as a result of this retrofit decreased from 22.1 degrees F to 15.5 degrees F.
Accession Number: 60802
Library Notes: NPL-1409 REV
Report Numbers: FS-5500-62389; DOE/GO-102014-4464

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