Guide to Installing High Efficiency Gas Hot Water Heaters InspectAPedia® -
High efficiency water heater suggestions for saving on water heating cost
How to obtain more hot water quantity, pressure, flow, at less cost
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This article discusses high efficiency gas-fired hot water heaters, characteristics, selection, installation, economy. Thanks to Carson Dunlop, a Toronto Home Inspection Firm and Home Inspection Educator, for permission to use sketches shown in this article.
Below we discuss other steps that can be taken to improve hot water quantity. And having a greater quantity of hot water also opens the way to taking steps to improve hot water pressure. (If we increase hot water pressure but lack adequate hot water quantity the result is we run out of hot water faster than ever.)
Install a New High Efficiency Type of Water Heater to Save Hot Water Cost
The water heater shown at page top was installed in our forensic laboratory. Using a power burner this water heater manages to extract a high enough percentage of the heat from its natural gas burner that the water heater exhaust can be vented directly to outdoors by means of a plastic pipe.
This particular water heater was manufactured by A.O. Smith but other companies also produce high-efficiency water heaters.
Here you can see a schematic of a high-efficiency gas-fired water heater in this sketch provided courtesy of Carson Dunlop, and you'll see a photo of a modern high-efficiency natural-gas fired water heater above..
Take a look at the Energy Guide sticker data, which measures anticipated energy cost in "Therms per year" (to avoid being confused by changing fuel prices among fuel types) to compare the relative operating costs of these appliances.
The water heater shown at left anticipates an average annual energy cost of about $146. U.S.
if your present source, such as a tankless coil or range boiler is inadequate you can increase hot water pressure and quantity and also to reduce hot water costs, you can install a separate oil or gas fired water heater, an indirect-fired water heater, perhaps an instantaneous water heater, or if you are located where electricity is less costly than these fossil fuels, perhaps an electrical hot water heater.
Select a larger capacity hot water tank tank, perhaps 40 gallons or 50gallons to increase the hot water quantity as well.
High efficiency oil or gas fired water heaters cost a bit more but can pay for themselves quickly considering the rapidly rising costs of home heating oil and natural gas.
Articles Describing Steps to Increase Hot Water Quantity
The articles listed below offer more details about steps one can take to increase hot water quantity, pressure, and flow in a building. Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.
Extra Tanks to Increase Hot Water- pre-heat your hot water absorbing ambient building heat or increase hot water quantity with cascaded, staged, multiple water heaters, possibly using more than one energy source
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Additional technical contributors & reference sources for this article are listed below.
Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.
Thanks to Alan Carson and Bob Dunlop, Carson Dunlop, Associates, Toronto, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education, publications, report writing materials, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
Arlene Puentes, an ASHI member and a licensed home inspector in Kingston, NY, and has served on ASHI national committees as well as HVASHI Chapter President. Ms. Puentes can be contacted at ap@octoberhome.com
AO Smith produces AO Smith water heaters in addition to Reliance, State, Maytag and others.
www.aosmith.com/prod/wpc.htm. AOS's gas water heater manuals offering advice and safety warnings about adding water heater insulation are available at
www.statewaterheaters.com/lit/im/res-Elec/184671-000.pdf and at
www.hotwater.com/lit/im/res_gas/184123-000.pdf
Rheem who also makes electric water heaters provides a manual for electric water heaters at
waterheating.rheem.com/content/resources/documents/use_care/ResElecProfessional.pdf. Rheem says, as do other water heater producers, that their water heaters
meet the "National Appliance Energy Conservation Act
standards with respect to insulation and
standby loss requirements making an
insulation blanket unnecessary"
Rheem also warns consumers that adding an insulation product [or making any other modification to their equipment] is likely to void the product warranty and may be unsafe:
"The manufacturer’s warranty does not
cover any damage or defect caused by
installation, attachment or use of
any type of energy saving or other
unapproved devices (other than those
authorized by the manufacturer) into, onto
or in conjunction with the water heater.
The use of unauthorized energy saving
devices may shorten the life of the water
heater and may endanger life and property.
The manufacturer disclaims any
responsibility for such loss or injury
resulting from the use of such
unauthorized devices "
Domestic and Commercial Oil Burners, Charles H. Burkhardt, McGraw Hill Book Company, New York 3rd Ed 1969.
National Fuel Gas Code (Z223.1) $16.00 and National Fuel Gas Code Handbook (Z223.2) $47.00 American Gas Association (A.G.A.), 1515 Wilson Boulevard, Arlington, VA 22209 also available from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. Fundamentals of Gas Appliance Venting and Ventilation, 1985, American Gas Association Laboratories, Engineering Services Department. American Gas Association, 1515 Wilson Boulevard, Arlington, VA 22209. Catalog #XHO585. Reprinted 1989.
The Steam Book, 1984, Training and Education Department, Fluid Handling Division, ITT [probably out of print, possibly available from several home inspection supply companies] Fuel Oil and Oil Heat Magazine, October 1990, offers an update,
Principles of Steam Heating, $13.25 includes postage. Fuel oil & Oil Heat Magazine, 389 Passaic Ave., Fairfield, NJ 07004.
The Lost Art of Steam Heating, Dan Holohan, 516-579-3046 FAX
Principles of Steam Heating, Dan Holohan, technical editor of Fuel Oil and Oil Heat magazine, 389 Passaic Ave., Fairfield, NJ 07004 ($12.+1.25 postage/handling).
"Residential Hydronic (circulating hot water) Heating Systems", Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
"Warm Air Heating Systems". Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
Heating, Ventilating, and Air Conditioning Volume I, Heating Fundamentals,
Boilers, Boiler Conversions, James E. Brumbaugh, ISBN 0-672-23389-4 (v. 1) Volume II, Oil, Gas, and Coal Burners, Controls, Ducts, Piping, Valves, James E. Brumbaugh, ISBN 0-672-23390-7 (v. 2) Volume III, Radiant Heating, Water Heaters, Ventilation, Air Conditioning, Heat Pumps, Air Cleaners, James E. Brumbaugh, ISBN 0-672-23383-5 (v. 3) or ISBN 0-672-23380-0 (set) Special Sales Director, Macmillan Publishing Co., 866 Third Ave., New York, NY 10022. Macmillan Publishing Co., NY
Installation Guide for Residential Hydronic Heating Systems
Installation Guide #200, The Hydronics Institute, 35 Russo Place, Berkeley Heights, NJ 07922
The ABC's of Retention Head Oil Burners, National Association of Oil Heat Service Managers, TM 115, National Old Timers' Association of the Energy Industry, PO Box 168, Mineola, NY 11501. (Excellent tips on spotting problems on oil-fired heating equipment. Booklet.)
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