Performance Testing of Alternative Blowing Agents for Foam Insulation of Residential Water Heaters.
Performance Testing of Alternative Blowing Agents for
Foam Insulation of Residential Water Heaters.
Fanney, A. H.; Zarr, R. R.
Appliance Manufacturer Conference and Exposition (AMCE).
Proceedings. September 27-29, 1999, Nashville, TN,
293-303 pp, 1999.
Sponsor: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