Hot Water Supply Standards

he Department of Energy published Department Circular 2020-12-0026 on February 19, 2021. This aims to promote the use of energy-efficient design and equipment for buildings with at least 10,000 square meters of total gross floor area or with at least 112.5 KVA of total connected electrical load.

The DOE promotes the use of steam to produce hot water when it is available. Heat exchangers and calorifiers can be used to get heat from steam to produce hot water. When steam is not available, direct fuel-fired heaters are preferred over electric water heaters. Solar water heaters with adequate storage are recommended to increase the use of renewable energy.

As the world's largest water heating company, A. O. Smith understands the significant energy demand for providing hot water. That is why A. O. Smith has been at the forefront of providing energy-efficient solutions to water heating. 

For steam-to-hot-water applications, A. O. Smith has well-insulated calorifier tanks with heat exchangers designed for steam.

For direct fuel-fired water heaters, A. O. Smith has both diesel and LPG-fired gas water heaters with high-efficiency ratings. A. O. Smith introduced the Cyclone Extra-High Efficiency Gas water heater in 1996. Its 94-98% efficiency rating exceeds the current DOE standard of 80-85% for direct-fired gas heaters.

For renewable energy applications, A. O. Smith has hybrid and split-type air-to-water heat pump water heaters that harvest heat from the air to produce hot water. Heat pump water heaters are ideal for the Philippine climate since they are highly efficient at high ambient temperature and humid climates. They run day and night, whatever is the weather. They can work even with the colder weather of Baguio and Tagaytay. Because of its availability, its potential for energy saving can be higher than solar water heaters.

For very large hotel and mall applications, A. O. Smith also has water-to-water heat pump water heaters that can recycle heat from the centralized AC chiller condenser to produce hot water with the least energy.

See below table for DOE thermal efficiency requirements and A. O. Smith high-efficiency solutions.

DOE Standards vs A. O. Smith High Efficiency
Equipment ClassDOE Required Thermal EfficiencyA. O. Smith High Efficiency
Electric storage water heaters99%260-400% or more using Heat Pumps
Commercial gas-fired storage heaters80%Up to 98%
Gas-fired tankless water heaters80%Up to 96%
Residential gas-fired storage heaters80%0.95 UEF (Uniform Energy Factor)
Hot water supply boilers80%Up to 98%


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