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Title: Technology Case Studies: Retrofit Integrated Space and Water Heating - Field Assessment

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. 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. 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:
Report Number(s):
Research Org:
NorthernSTAR Building America Partnership
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Building Technologies Office (EE-5B) (Building America)
Country of Publication:
United States
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