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Title: Retrofit Integrated Space & Water Heating: Field Assessment, Minneapolis, Minnesota (Fact Sheet)

This project analyzed combined condensing water heaters or boilers and hydronic air coils to provide high efficiency domestic hot water and forced air space heating. Called 'Combi' systems, they provided similar space and water heating performance less expensively than installing two condensing appliances. The system's installed costs were cheaper than installing a condensing furnace and either a condensing tankless or condensing storage water heater. However, combi costs must mature and be reduced before they are competitive with a condensing furnace and power vented water heater (EF of 0.60). Better insulation and tighter envelopes are reducing space heating loads for new and existing homes. For many homes, decreased space heating loads make it possible for both space and domestic water heating loads to be provided with a single heating plant. These systems can also eliminate safety issues associated with natural draft appliances through the use of one common sealed combustion vent.
Publication Date:
OSTI Identifier:
1132127
Report Number(s):
DOE/GO-102014-4379
KNDJ-0-40338-00
DOE Contract Number:
AC36-08GO28308
Resource Type:
Technical Report
Resource Relation:
Related Information: Building America Case Study: Technology Solutions for New and Existing Homes, Building Technologies Office (BTO)
Research Org:
National Renewable Energy Laboratory (NREL), Golden, CO.
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy Building Technologies Program
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION RESIDENTIAL; RESIDENTIAL BUILDINGS; NORTHERNSTAR; BUILDING AMERICA; COMBI HEATING SYSTEMS; FORCED AIR COMBI SYSTEMS; HYDRONIC AIR HANDLERS; BOILER BASED COMBI SYSTEMS; TANKLESS WATER HEATER BASED COMBI SYSTEMS; STORAGE WATER HEATER BASED COMBI SYSTEMS; DHW PERFORMANCE; COMBI SYSTEM SUMMER EFFICIENCY; DUAL INTEGRATED APPLIANCES; DIRECT VENT BURNER; Building America