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DOE OSTI · 1096690

Optimizing Hydronic System Performance in Residential Applications

Arena, L.·Faakye, O.
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Abstract

Even though new homes constructed with hydronic heat comprise only 3% of the market (US Census Bureau 2009), of the 115 million existing homes in the United States, almost 14 million of those homes (11%) are heated with steam or hot water systems according to 2009 US Census data. Therefore, improvements in hydronic system performance could result in significant energy savings in the US. When operating properly, the combination of a gas-fired condensing boiler with baseboard convectors and an indirect water heater is a viable option for high-efficiency residential space heating in cold climates. Based on previous research efforts, however, it is apparent that these types of systems are typically not designed and installed to achieve maximum efficiency. Furthermore, guidance on proper design and commissioning for heating contractors and energy consultants is hard to find and is not comprehensive. Through modeling and monitoring, CARB sought to determine the optimal combination(s) of components - pumps, high efficiency heat sources, plumbing configurations and controls - that result in the highest overall efficiency for a hydronic system when baseboard convectors are used as the heat emitter. The impact of variable-speed pumps on energy use and system performance was also investigated along with the effects of various control strategies and the introduction of thermal mass.

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32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATIONAFUEBaseboardBuffer TankBuilding AmericaBuildingsCARBCondensing BoilersCyclingEfficiencyGas-FiredHot WaterHVACHydronic SystemsIndirect TankModulatingOptimizationRecoveryResidentialResidential BuildingsReturn TemperatureStandby LossesThermostat SetbackVariable Speed Pumps

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Arena, L., Faakye, O.. 2013-10-01. Optimizing Hydronic System Performance in Residential Applications. https://doi.org/10.2172/1096690

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