NIST Time|NIST Home|About NIST|Contact NIST

HomeAll Years:AuthorKeywordTitle2005-2010:AuthorKeywordTitle

Performance Testing of Alternative Blowing Agents for Foam Insulation of Residential Water Heaters.

pdf icon Performance Testing of Alternative Blowing Agents for Foam Insulation of Residential Water Heaters. (1044 K)
Fanney, A. H.; Zarr, R. R.

Appliance Manufacturer Conference and Exposition (AMCE). Proceedings. September 27-29, 1999, Nashville, TN, 293-303 pp, 1999.


Department of Energy, Washington, DC


heaters; water heaters; blowing agents; insulation; residential buildings; physical properties; thermal conductivity; polyurethane foams


The U.S. Department of Energy (DOE) has requested the assistance of the Pacific Northwest National Laboratory to conduct analyses to determine if the energy efficiency requirements for electric, gas- and oil-fired residential water heaters should be revised. (Pacific Northwest National Laboratory is operated for DOE by Battelle Memorial Institute.) The performance of residential water heaters is measured by the Energy Factor (EF), a metric which accounts for both the efficiency of energy transfer to the water and the heat losses from the stored hot water to the environment. Residential water heaters are typically manufactured with 1 to 2 inches of foam insulation blown into the jacket with hydrochlorofluorocarbons (HCFCs) such as HCFC-141b. The insulation reduces the heat losses from the storage tank of the water heater, thus playing a role in meeting the DOE energy factor requirements. In accordance with the Montreal Protocol on ozone-depleting substances, the U.S. Environmental Protection Agency (EPA) has scheduled the phase-out of HCFC-141b for January 1,2003. Several alternatives are being evaluated for blowing foam insulation. Examples of alternative materials being considered include hydrofluorocarbons (HFCs) such as HFC-245fa, HFC-356mffm, HFC-134a; cyclopentane; or water-based foams. Because there is little data on the performance of these foams in residential water heater applications, DOE initiated a study to evaluate their comparative performance. This paper reports on the details of the testing and evaluation of water heater performance using the alternative foam blowing agents. The results of this study are being used by DOE to evaluate the engineering and cost effectiveness of using alternative foam blowing agents for insulating water heaters in its revision of the residential water heater energy efficiency standards.