HEY! THAT'S HOT!

GOAL:: The student will discover the cost of hot water and will recognize the need to use hot water and water heaters more efficiently.

OBJECTIVES:: The student will be able to:; 1. Discuss the cost of operating a water heater.; 2. List actions that can help increase the efficiency of a water heater.; 3. Discuss changes in personal habits that can cut down on the use of hot water.

LESSON / INFORMATION:: Of the total energy budget for the typical home, 20% of the money spent on home energy is spent in the operation of the water heater.; It is estimated that the energy required to heat water can be reduced as much as 40% by following recommended energy conservation practices.

ACTIVITY 1:: 1. If a family's average energy bill is $110 per month, how much of this is spent on hot water?________; 2. If 40% of this money could be saved, how much would be saved each month on water heating?___________; 3. How much could be saved in a year?____________________; Some recommended practices to help reduce energy spent on hot water heating include the following:; 1. Try to prevent sediment from collecting at the bottom of the heater. Sediment separates water from the heating element and forces the water heater to work harder. Drain several gallons of water from the tank each month to reduce sediment. If this is impossible, then flushing the hot water tank once a year is desirable. Be careful when draining or flushing the tank; the water will be very hot.; 2. Most water heaters are set at 140°F. This is generally too high; 110°F to 120°F is usually hot enough. Dishwashers have built-in heaters to heat water to higher temperatures if necessary. This lower temperature setting alone could save up to $45 a year on the cost of heating water.; 3. Locate the water heater in a utility room and away from items such as the air conditioner or refrigerator. The heat given off by the water heater could force these other appliances to work harder.; 4. Insulate the water heater with some type of insulation, preferably an insulation refit kit. These kits are readily available, easily installed, and inexpensive (typical cost $12). Blanket type insulation is also available to wrap the tank. Do not use the blanket type on a gas water heater. The fitted type, with an opening near the pilot light and controls, is recommended.; 5. Place the water heater so that the length of pipe from the heater to the distribution point is less than 20 feet. In a large house, it is better to have two water heaters than longer lengths of pipe. Pipes carrying water from the heater should also be insulated.; 6. It is important to select a water heater that is soundly constructed, has built-in insulation, and provides information on energy efficiency and insulation type on the unit.; 7. Insulate all hot water lines; cold water lines on exterior walls and in the attic should also be insulated.; 8. When the water heater is being installed, make sure heat traps or one-way valves are installed on both the hot and cold water lines to cut down on losses through the pipes. Without one-way valves, hot water rises and allows heat from the water heater to be lost.; 9. A supplementary demand water heater should be considered if there is a high usage faucet in the house.; 10. Timers with set back features should be installed on all hot water tanks. These can keep the unit from operating 24 hours a day and prevent the water heater from working during times of little use.; 11. In houses with heat pumps, the installation of a waste heat recovery unit could provide free hot water. The line carrying hot freon from the cooling sytem is placed within the water line which transfers heat to the water that is circulated back to the hot water tank. Although the heat recovery unit may cost from $400 to $600, the unit may reduce hot water costs by 50%.; After the proper water heater is purchased, placed, and protected, there is still much that can be done to save on the cost of hot water. Your hot water consumption habits can be improved.

ACTIVITY 2:: List some BAD habits you have that waste hot water and increase home energy costs.; 1.__________________________________________________________; 2.__________________________________________________________; 3.__________________________________________________________; Some suggestions to help break these bad habits and reduce the amount of money spent on heating water include:; 1. Repair leaky faucets. One leaky faucet can waste 6000 gallons of water a year!; 2. When leaving home for more than two full days, set the thermostat on the water heater to a low setting.; 3. When washing dishes or clothes -- or yourself -- use as little water as necessary. Fill the sink once for washing and do not let the water run continuously while rinsing.; 4. Use cold water whenever possible -- when washing most types of clothing, when using the garbage disposal, when rinsing dishes.; 5. Take a shower instead of a bath. This can save up to 10 gallons of water. By adding a flow restrictor device to the showerhead, even more hot water can be saved.; 6. To reduce sediment build up, drain a gallon of water from the tank each month. If this is not possible, drain the entire hot water tank at least once a year.

RESOURCES:: Building Energy Efficient Homes in Louisiana. Louisiana Department of Natural Resources, Baton Rouge, LA, n.d.; Homeowners' Energy Conservation. Louisiana Department of Natural Resources, Baton Rouge, LA, 1981.; How to Cut Your Hot Water Expenses. Louisiana Department of Natural Resources, Baton Rouge, LA, n.d.; Free Hot Water. SLEMCO, Lafayette, LA, n.d.; Slemco Builder's Guide: Design One for Energy Efficient Construction. SLEMCO, Lafayette, LA, 1988.

INFORMATION CHECK

Fill in the blanks with the word or phrase that best completes the statement. Some of the answers will not be used.

20%

sediment

flow restrictor

30%

fiberglass

shower cap

40%

10 feet

garbage disposal

120°F

20 feet

days

140°F

refrigerator

weeks

160°F

range / oven

leaky faucets

1. Up to _____% can be saved on water heating costs by following the recommended practices.

2. Pipe should only run _____ feet from the water heater to its destination.

3. ____________________ may waste up too 6000 gallons of water a year.

4. Do not place the water heater near the ________________.

5. Many water heaters are set at _____°F, which is really a bit too high.

6. Most water heaters can safely be lowered to _____ °F.

7. Use cold water when using the ____________________.

8. ____________________ placed around the water heater can save up to $45 a year on water heating costs.

9. _____% of the home energy budget is spent on the heating water.

10. Clean _______________ from the bottom of the tank to allow water to be heated more efficiently.

11. If leaving home for at least two full __________, be sure to lower the setting on the water heater.

12. Always use a ____________________ when taking a shower to save even more hot water.

TEACHER'S NOTES
ACTIVITY 1:: 1. $22; 2. $8.80; 3. $105.60

ACTIVITY 2:: Look for bad habits such as:

DEFINITIONS:: 1. Insulation -; This is a material that has a high resistance to heat flow. In relation to the water heater, insulation placed around the heater will keep the heat in to warm the water and will not let heat escape into surrounding areas.; 2. Sediment -; This is a collection of minerals at the bottom of the water heater. Sediment can cover the heating element and divert heat from the water. Thus, it is important to reduce sediment in the water heating system.

ANSWERS TO INFORMATION CHECK:: 1. 40%; 2. 20 feet; 3. leaky faucets; 4. refrigerator; 5. 140°F; 6. 120°F; 7. garbage disposal; 8. fiberglass; 9. 20%; 10. sediment; 11. days; 12. flow restrictor

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