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Traditional Water Heaters
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What is the "SAFE" minimum temperature
a water heater should be set?
Traditional Water Heaters
Traditional domestic gas water heater designs have changed significantly due to the introduction of safety and energy efficiency standards. The electric and oil fired water heaters have changed somewhat, but not as dramatically as gas water heaters. Sizes are available in 30, 40, 50, 60 and 70 US gallon capacities mean no more waiting for hot water.
Gas water heaters were subject to a new code and standard that resulted in all manufacturers having to redesign their tanks to be Flammable Vapour Ignition Resistant (FVIR). This to eliminate the potential for the pilot light (ignition source) from igniting flammable vapours from household products that may be used or spilled in the area of the water
heaters. As such, all gas water heaters are now made with some form of safety protection device. On John Wood water heaters this safety device is called the "Flame Guard" system. There is a small thermal sensor located inside the combustion zone of the water heater and if it senses a flammable vapour incident it shuts off the gas flow to the burner and pilot. The flammable vapour that is ignited can only travel into the water heaters combustion zone and not back out. This is accomplished with a special inlet air design. The Flame Guard system was Popular Science's "Best of What's New" award winner, the US Consumer Product Safety Commission also recognized the product development with the "Chairman's Commendation."
How do I know what size of residential domestic water heater to purchase?
Let's figure out what you need.
| Number of people in your household | ______ |
| Number of baths and showers per day (count .5 for each) |
______ |
| Washing machine? (if yes, count.5 point) |
______ |
| Automatic dishwasher? (if yes, count .5 point) |
______ |
| Spa, whirlpool or oversize bath? (count 1 point for each) |
______ |
| Your Total | ______ |
| Gas | Size Required | Electric | Size Required |
| Your Total | Your Total | ||
| 3 or less 3-5 5-6 7 or more |
30 gallon 40 gallon 50 gallon 60 gallon |
4 or less 5-7 8 or more |
40 gallon 60 gallon 2x40 gallon |
These guidelines are for average family usage. But do family members often have several baths or showers in a row? Do you wash clothes or dishes at the same time that people are bathing? If so, you may need the next largest size of water heater. In addition you should look at your plans for the future. Are you considering adding a bathroom, spa or dishwasher? Is your family size likely to change? Considering these factors now will ensure that your water heater never leaves you cold.
When paying your gas or electric utility bill, do you think it's too much? A good rule of thumb is to take your energy bill, divide the total amount by seven. The result is the approximate amount you are paying just to "heat" your water. You may think that this cost is a very small price to pay for the conveniences of hot water. However, costs add up over the period of a year. Taking steps to decrease wasteful water consumption and usage now will result in reduced heating costs and make your system more energy efficient.
A Few Simple Measures to Reduce the Amount of Hot Water used:
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Repair leaks in faucets and showerheads
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Turn hot-water faucets off while shaving or brushing your teeth, etc.
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Reduce the time spent in the shower
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Install low-flow showerheads and faucet aerators
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Always operate the dishwasher with full loads
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Wash only full loads of laundry using cold or warm water, rather than hot water
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Adjust water levels for smaller loads of laundry
Saving money by lowering the water heaters temperatures to 120ºF could be unsafe and pose a major hazard. Further, you might still find yourself running out of hot water, conditions that are unsatisfactory to most homeowners. If you want further information about how to adjust the thermostat on your water heater consult the owners manual or contact Manitoba Hydro and ask for their booklet number 7 on Water Heaters," there is load of valuable information and tips. But, CAUTION. the temperature reduction of the water heaters below 135ºF is unsafe.
For more info read Water Heaters Part 1 and Part 2 in the News Releases section.
| Aero Water Heaters | ||
| John Wood | ||
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Rheem |







