This facility has high DHW use for xxx, with heat provided by a xxx.
The existing heater tank or boiler/tank combination should be replaced with one or more AO Smith Cyclone condensing heater tanks. This system operates at over 90% seasonal efficiency, and has been proven effective even in hard water areas.
Where electric heater tanks exist, the savings come from substituting an expensive heat source for a less expensive source (natural gas). Electricity is almost four times as expensive as the equivalent heating value of natural gas.
Where a regular atmospheric gas heater tank exists, savings come from effectively doubling the heating efficiency (from 45% to 90% efficiency).
This recommendation is in accordance with Section 7.6 Service Water Heating Systems of the ASHRAE Standard on Energy Conservation in Existing Buildings.1
Issues and Concerns
1 ASHRAE Standard ANSI/ASHRAE/IESNA 100-1995 – Energy Conservation in Existing Buildings is an approved standard of the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., the Illuminating Engineering Society of North America and the American National Standards Institute.
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