Here are links to all the articles below!
Rinnai On-Demand Water Heaters in the Speculative Building Market
Water Heater Types
Water Heating Conservation Tips
More on Efficient Hot Water Usage
5 Reasons Not to Install Your Own Water Heater
Choosing a Water Heater
Water Heater FAQ's
Setting the Temperature on Your Water Heater
Installing an Insulation Blanket on an Electric Hot Water Tank
Selecting a New Water Heater
Summary: This fact sheet will help you select an energy-efficient water heater for your home. Many homeowners wait until their water heater fails before shopping for a replacement. Because they are in a hurry to regain their hot water supply, they are often unable to take the time to shop for the most energy-efficient unit for their specific needs. This is unfortunate because the cost of purchasing and operating a water heater can vary greatly, depending on the type, brand, and model selected and on the quality of the installation. To avoid this scenario, you might want to do some research now before you are faced with an emergency purchase. Familiarize yourself today with the options that will allow you to make an informed decision when the need to buy a new water heater arises.
Types of Water Heaters Available
Within the last few years, a variety of water heaters have become available to consumers. The following types of water heaters are now on the market: conventional storage, demand, heat pump, tankless coil, indirect, and solar. It is also possible to purchase water heaters that can be connected to your home's space-heating system.
Storage Water Heaters
A variety of fuel options are available for conventional storage water heaters electricity, natural gas, oil, and propane. Ranging in size from 20 to 80 gallons (75.7 to 302.8 liters), storage water heaters remain the most popular type for residential heating needs in the United States. A storage heater operates by releasing hot water from the top of the tank when the hot water tap is turned on. To replace that hot water, cold water enters the bottom of the tank, ensuring that the tank is always full.
Because the water is constantly heated in the tank, energy can be wasted even when no faucet is on. This is called standby heat loss. Newer, more energy-efficient storage models can significantly reduce the amount of standby heat loss, making them much less expensive to operate. To determine the most energy-efficient model, consult the EnergyGuide label required on storage water heaters. EnergyGuide labels indicate either the annual estimated cost of operating the system or energy efficiency ratings.
Demand Water Heaters
It is possible to completely eliminate standby heat losses from the tank and reduce energy consumption 20% to 30% with demand (or instantaneous) water heaters, which do not have storage tanks. Cold water travels through a pipe into the unit, and either a gas burner or an electric element heats the water only when needed. With these systems, you never run out of hot water. But there is one potential drawback with demand water heaters -- limited flow rate. Typically, demand heaters provide hot water at a rate of 2 to 4 gallons (7.6 to 15.2 liters) per minute. This flow rate might suffice if your household does not use hot water at more than one location at the same time (e.g., showering and doing laundry simultaneously). To meet hot water demand when multiple faucets are being used, demand heaters can be installed in parallel sequence. Although gas-fired demand heaters tend to have higher flow rates than electric ones, they can waste energy even when no water is being heated if their pilot lights stay on. However, the amount of energy consumed by a pilot light is quite small.
Heat Pump Water Heaters
Heat pump water heaters use electricity to move heat from one place to another instead of generating heat directly. To heat water for homes, heat pump water heaters work like refrigerators in reverse. Heat pump water heaters can be purchased as integral units with built-in water storage tanks or as add-ons that can be retrofitted to an existing water heater tank. These systems have a high initial cost. They also require installation in locations that remain in the 40 degree to 90 degree F (4.4 degrees to 32.2 degrees C) range year-round and contain at least 1000 cubic feet (28.3 cubic meters) of air space around the water heaters. To operate most efficiently, they should be placed in areas having excess heat, such as furnace rooms. They will not work well in a cold space.
Tankless Coil and Indirect Water Heaters
A home's space-heating system can also be used to heat water. Two types of water heaters that use this system are tankless coil and indirect. No separate storage tank is needed in the tankless coil water heater because water is heated directly inside the boiler in a hydronic (i.e., hot water) heating system. The water flows through a heat exchanger in the boiler whenever a hot water faucet is turned on. During colder months, the tankless coil works well because the heating system is used regularly. However, the system is less efficient during warmer months and in warmer climates when the boiler is used less frequently. A separate storage tank is required with an indirect water heater. Like the tankless coil, the indirect water heater circulates water through a heat exchanger in the boiler. But this heated water then flows to an insulated storage tank. Because the boiler does not need to operate frequently, this system is more efficient than the tankless coil. In fact, when an indirect water heater is used with a highly efficient boiler, the combination may provide one of the least expensive methods of water heating.
Solar Water Heaters
Through specially designed systems, energy from the sun can be used to heat water for your home. Depending on climate and water use, a properly designed, installed, and maintained solar water heater can meet from half to nearly all of a home's hot water demand. Two features, a collector and a storage tank, characterize most solar water heaters. Beyond these common features, solar water-heating systems can vary significantly in design. The various system designs can be classified as passive or active and as direct (also called open loop) or indirect (also called closed loop). Passive systems operate without pumps and controls and can be more reliable, more durable, easier to maintain, longer lasting, and less expensive to operate than active systems. Active solar water heaters incorporate pumps and controls to move heat-transfer fluids from the collectors to the storage tanks. Both active and passive solar water-heating systems often require conventional water heaters as backups, or the solar systems function as preheaters for the conventional units. A direct solar water-heating system circulates household water through collectors and is not appropriate in climates in which freezing temperatures occur. An indirect system should not experience problems with freezing because the fluid in the collectors is usually a form of antifreeze. If you are considering purchasing a solar water-heating system, you may want to compare products from different manufacturers. The Solar Rating and Certification Corporation provides a benchmark for comparing the performance of some solar water heating systems. The SRCC publishes performance ratings of both solar water-heating systems and individual solar collectors. These published ratings are the results of independent, third-party laboratory testing of these products. All systems and collectors that have been certified by the SRCC will bear the SRCC label. Keep in mind, though, that simply having an SRCC label does not imply that the product has a superior performance. Carefully compare SRCC label information on different brands and models to ensure that you are fully aware of projected performance. The Florida Solar Energy Center also provides information on solar manufacturers and contractors. It also maintains solar equipment testing facilities and publishes performance ratings for solar water heating systems. Just choosing a solar water heater with good ratings is not enough, though. Proper design, sizing, installation, and maintenance are also critical to ensure efficient system performance. Although the purchase and installation prices of solar water heaters are usually higher than those of conventional types, operating costs are much lower. For more information about solar water-heating systems, contact the Energy Efficiency and Renewable Energy Clearinghouse.
Criteria for Selection
As with any purchase, balance the pros and cons of the different water heaters in light of your particular needs. There are numerous factors to consider when choosing a new water heater. This publication has already described different system configurations. Some other considerations are capacity, efficiency, and cost.
Determining Capacity
Although some consumers base their purchases on the size of the storage tank, the peak hour demand capacity, referred to as the first-hour rating (FHR) on the EnergyGuide label, is actually the more important figure. The FHR is a measure of how much hot water the heater will deliver during a busy hour, and it is required by law to appear on the unit's EnergyGuide label. Therefore, before you shop, estimate your household's peak hour demand and look for a unit with an FHR in that range. Gas water heaters have higher FHRs than electric water heaters of the same storage capacity. Therefore, it may be possible to meet your water-heating needs with a gas unit that has a smaller storage tank than an electric unit with the same FHR. More efficient gas water heaters use various nonconventional arrangements for combustion air intake and exhaust. These features, however, can increase installation costs.
Rating Efficiency
Once you have decided what type of water heater best suits your needs, determine which water heater in that category is the most fuel efficient. The best indicator of a heater's efficiency is its Energy Factor (EF), which is based on recovery efficiency (i.e., how efficiently the heat from the energy source is transferred to the water), standby losses (i.e., the percentage of heat lost per hour from the stored water compared to the heat content of the water), and cycling losses. The higher the EF, the more efficient the water heater. Electric resistance water heaters have an EF between 0.7 and 0.95; gas heaters have an EF between 0.5 and 0.6, with some high-efficiency models around 0.8; oil heaters range from 0.7 to 0.85; and heat pump water heaters range from 1.5 to 2.0. Product literature from manufacturers usually gives the appliance s EF rating. If it does not, you can obtain it by contacting an appliance manufacturer association (see Source List). Some other energy efficiency features to look for are tanks with at least 1.5 inches (3.8 centimeters) of foam insulation and energy efficiency ratings shown on the EnergyGuide labels.
Comparing Costs
Another factor uppermost in many consumers' minds is cost, which encompasses purchase price and lifetime maintenance and operation expenses. When choosing among different models, it is wise to analyze the life-cycle cost -- the total of all costs and benefits associated with a purchase during its estimated lifetime. More information on conducting life-cycle cost analyses is available from EREC. Units with longer warranties usually have higher price tags, though. Often, the least expensive water heater to purchase is the most expensive to operate.
Repair leaky faucets promptly; a leaky faucet wastes gallons of water in a short period.
Insulate your electric hot-water storage tank and pipes, but be careful not to cover the thermostat.
Insulate your gas or oil hot-water storage tank and pipes, but be careful not to cover the water heater's top, bottom, thermostat, or burner compartment; when in doubt, get professional help.
Install non-aerating low-flow faucets and showerheads.
Buy a new water heater. While it may cost more initially than a standard water heater, the energy savings will continue during the lifetime of the appliance.
Although most water heaters last 10-15 years, it's best to start shopping for a new one if yours is more than 7 years old. Doing some research before your heater fails will enable you to select one that most appropriately meets your needs.
Lower the thermostat on your water heater; water heaters sometimes come from the factory with high temperature settings, but a setting of 115°F provides comfortable hot water for most uses.
Drain a quart of water from your water tank every 3 months to remove sediment that impedes heat transfer and lowers the efficiency of your heater. The type of water tank you have determines the steps to take, so follow the manufacturer's advice.
If you heat with electricity and live in a warm and sunny climate, consider installing a solar water heater. The solar units are environmentally friendly and can now be installed on your roof to blend with the architecture of your house.
Take more showers than baths. Bathing uses the most hot water in the average household. You use 15-25 gallons of hot water for a bath, but less than 10 gallons during a 5-minute shower.
| 1. You may not select the right water heater for your needs and specifications. |
| It’s not as simple as replacing a 30-gallon hot water heater with another 30-gallon model. There are thousands of sizes and options available today. Fuel source, energy efficiency, fast recovery, venting and anticipated demand must all be considered in order to determine the correct model. |
| 2. Local codes and ordinances may not permit self-installation. |
| Regulations governing water heater installation vary by city. Professional contractors are familiar with the rules and regulations in each city they service. |
| 3. Installation requires materials and knowledge most homeowners don’t have on hand. |
| Installation involves much more than just attaching a water line. A professional contractor arrives with all the fittings, pipes, parts, tools, venting materials and valves needed to install the job correctly the first time. Most also include removal and disposal of your old water. |
| 4. A professional contractor may be able to repair your hot water heater instead of replace it. |
| If your hot water heater’s problem is diagnosed as a defective heating element or faulty valve, it can be fixed. A contractor’s experience is the difference between a minor repair and unnecessary investment in a new water heater. |
| 5. Contractors provide safety and security you can live with. |
Water heating is typically the third largest energy expense in your home (after space heating and cooling). It typically accounts for about 14% of your utility bill. If your gas water heater is more than 10 years old, it probably has an efficiency no higher than 50%. An old water heater can operate for years at very low efficiency before it finally fails. One way to reduce water heating costs would be to replace your old water heater with a new, higher-efficiency mode
About Water Heating Efficiency
A water heater's efficiency is measured by its energy factor (EF). EF is based on recovery efficiency, standby losses, and cycling losses. The higher the EF, the more efficient the water heater. Electric resistance water heaters have an EF ranging from 0.7 and 0.95; gas water heaters from 0.5 to 0.6, with a few high-efficiency models ranging around 0.8; oil water heaters from 0.7 and 0.85; and heat pump water heaters from 1.5 to 2.0.
Although many consumers make water heater purchase decisions based only on the size of the storage tank, the first-hour rating (FHR), provided on the Energy Guide label, is actually more important. The FHR is a measure of how much hot water the heater will deliver during a busy hour. The FHR is required by law to appear on the unit's Energy Guide label. Therefore, before you buy a water heater, estimate your household's peak-hour demand and look for a unit with an FHR in that range. And beware that a larger tank doesn't necessarily mean a higher FHR.
Tips for Buying a New Water Heater
Point-of-use water heaters:
Point-of-use water heaters are also known as "tankless" heaters because they have no (or only a tiny) storage tank. They are relatively small units that provide hot water on demand. They use gas or electricity for fuel, and can be installed near demand points, such as under kitchen sinks. They are often more expensive than a conventional water heater, but can cost less to operate since they don't maintain a tankfull of hot water when not in use. A tankless heater typically provides 1-2 gallons of hot water per minute. Before installing a tankless water heater in your home, make sure its reduced capacity will be adequate for your needs.
Solar water heaters:
A solar water heater typically includes collectors mounted on the roof or in a clear area of the yard, a separate storage tank near the conventional heater in the home, connecting pipe, and a controller. Solar water heaters can reduce the annual fuel cost of supplying hot water to your home by more than half. Throughout the year, the solar system preheats the water before it reaches the conventional water heater. During the summer, it may provide all the required heat.
Desuperheaters:
A desuperheater is an attachment to your air conditioner or heat pump that allows waste heat from that device to help heat domestic water. In hot climates, a desuperheater can provide most of a home's hot water needs during the summer.
What is the average lifetime of a gas water heater?
The average lifetime of gas water heater is 9 years. The range is 5-14 years.
How is FHR and Therms used to compare the efficiency of water heaters?
The first hour rating (FHR) tells you the number of gallons per hour of hot water. Therms relate to the gas consumption of water heater. When you are shopping for hot water heater, compare the energy factor on the energy guide label. FHR and Therms are not sufficient to calculate the energy factor. Also remember to compare water heaters of equal capacity and FHR.
What efficiency standard does a dual use residential water heater need to meet as a water heater or a boiler (used for both potable water and space heating purposes)?
For a dual unit, it must meet the efficiency standard requirements of both applications. Your local building department may have additional requirements for such units.
What is a hot water recirculating system?
A "hot water re-circulating" system usually refers to a domestic hot water system that circulates the heated water through the house continuously so as to eliminate or shorten the delay in hot water reaching the faucet after the user turns it on. These systems are most common in multifamily or large building applications where otherwise the delays would be truly unacceptable. They can be real energy hogs if the pipes aren't well insulated.
How do I choose the best electric or gas tankless water heater for my home (2300 sq. ft.)?
Sizing of hot water heaters should be based on the number of occupants and their peak hour water demand and not on the size of the house.
Are tankless water heaters more efficient?
Tankless water heater efficiencies are not addressed by the Federal standards. Check the EREC fact sheet at http://www.eren.doe.gov/consumerinfo/refbriefs/bc1.html for additional resources.
The next time you pay your utility bill, try one simple calculation. Divide the total amount by seven. The result is the amount you spend to heat your water. (If you receive separate utility bills for gas and electricity, use the gas bill for this calculation if you have a gas water heater; use the electric bill if you have an electric water heater.) Of course, you may think this cost is a small price to pay for the convenience of a hot shower. But during the course of a year, this cost adds up. And when you consider that 95 million households in this country pay the same percentage, it is easy to see how much money--and energy--is used to heat water.
Several measures can help you decrease water-heating costs in your home. Some specific actions include reducing the amount of hot water used, making your water-heating system more energy efficient, and using off-peak power to heat water.
Reducing the Amount of Hot Water Used
Generally, four destination points in the home are recognized as end uses for hot water: faucets, showers, dishwashers, and washing machines. Now, you do not have to take cold showers, dine on dirty dishes, or wear dirty clothes to reduce your hot-water consumption. Less radical measures are available that will be virtually unnoticeable once you apply them.
Simply repairing leaks in faucets and showers can save hot water. A leak of one drip per second can cost $1 per month, yet could be repaired in a few minutes for less than that. And some apparently insignificant steps, when practiced routinely at your household, could have significant results. For example, turning the hot-water faucet off while shaving or brushing your teeth, as opposed to letting the water run, can also reduce water-heating costs. Another option is limiting the amount of time you spend in the shower.
Other actions may require a small investment of time and money. Installing low-flow showerheads and faucet aerators can save significant amounts of hot water. Low-flow showerheads can reduce hot-water consumption for bathing by 30%, yet still provide a strong, invigorating spray. Faucet aerators, when applied in commercial and multifamily buildings where water is constantly circulated, can also reduce water-heating energy consumption.
Older showerheads deliver 4 to 5 gallons (15.1 to 18.9 liters) of water per minute. However, the Energy Policy Act of 1992 sets maximum water flow rates at 2.5 gallons (9.5 liters) per minute at a standard residential water pressure of 80 pounds per square inch (552 kilopascals).
A quick test can help you determine if your shower is a good candidate for a showerhead replacement. Turn on the shower to the normal pressure you use, hold a bucket that has been marked in gallon increments under the spray, and time how many seconds it takes to fill the bucket to the 1-gallon (3.8-liter) mark. If it takes less than 20 seconds, you could benefit from a low-flow showerhead. A top-quality, low-flow showerhead will cost $10 to $20 and pay for itself in energy saved within 4 months. Lower quality showerheads may simply restrict water flow, which often results in poor performance.
Because of the different Uses of bathroom and kitchen faucets, you may need to have different water flow rates in each location. For bathroom faucets, aerators that deliver 0.5 to 1 gallon (1.9 to 3.8 liters) of water per minute may be sufficient. Kitchen faucets may require a higher flow rate of 2 to 4 gallons (7.6 to 15.1 liters) per minute if you regularly fill the sink for washing dishes. On the other hand, if you tend to let the water run when washing dishes, the lower flow rate of 0.5 to 1 gallon per minute may be more appropriate. Some aerators come with shut-off valves that allow you to stop the flow of water without affecting the temperature.
A relatively common assumption is that washing dishes by hand saves hot water. However, washing dishes by hand several times a day could be more expensive than operating some automatic dishwashers. If properly used, an efficient dishwasher can consume less energy than washing dishes by hand, particularly when you only operate the dishwasher with full loads.
The biggest cost of operating a dishwasher comes from the energy required to heat the water before it ever makes it to the machine. Heating water for an automatic dishwasher can represent about 80% of the energy required to run this appliance.
Average dishwashers use 8 to 14 gallons (30.3 to 53 liters) of water for a complete wash cycle and require a water temperature of 140 degrees F (60 degrees C) for optimum cleaning. But setting your water heater so high could result in excessive standby heat loss. This type of heat loss occurs because water is constantly heated in the storage tank, even when no hot water is used. Furthermore, a water heater temperature of 120 degrees F (48.9 degrees C) is sufficient for other uses of hot water in the home.
The question, then, is must you give up effective cleaning for hot-water energy savings? The answer is no. A "booster" heater can increase the temperature of the water entering the dishwasher to the 140 degrees F recommended for cleaning. Some dishwashers have built-in boosters that will automatically raise the water temperature, while others require manual selection before the wash cycle begins. A booster heater can add about $30 to the cost of a new dishwasher but should pay for itself in water-heating energy savings in about 1 year if you also lower your water heater temperature. Reducing the water heater temperature is not advisable, however, if your dishwasher does not have a booster heater.
Another feature that reduces hot-water use in dishwashers is the availability of cycle selections. Shorter cycles require less water, thereby reducing the energy cost. The most efficient dishwasher currently on the market can cost half as much to operate as the most inefficient model. If you are planning to purchase a new dishwasher, check the EnergyGuide labels and compare the approximate yearly energy costs among brands. Dishwashers fall into one of two categories: compact capacity or standard capacity. Although compact-capacity dishwashers may appear to be more energy efficient, they hold fewer dishes and may force you to use the appliance more frequently than you would use a standard-capacity model. In this case, your energy costs could be higher than with the standard-capacity dishwasher.
Like dishwashers, much of the cost--up to 90%--of operating washing machines is associated with the energy needed to heat the water. Unlike dishwashers, washing machines do not require a minimum temperature for optimum cleaning. Either cold or warm water can be used for washing most laundry loads; cold water is always sufficient for rinsing. Make sure you follow the cold-water washing instructions for your particular laundry detergent. Washing only full loads is another good rule of thumb for reducing hot-water consumption in clothes washers.
As you would for dishwashers, consult the Energy Guide labels when shopping for a new washing machine. Inefficient washing machines can cost three times as much to operate as efficient machines. Select a machine that allows you to adjust the water temperature and water levels for the size of the load. Also, front-loading machines use less water and, consequently, less energy than top loaders. However, in this country, front loaders are not as widely available as top loaders. Keep in mind that the capacity of front loaders may be smaller than that of most top-loading machines.
Smaller capacity washing machines often have better Energy Guide ratings. However, a reduced capacity might cause you to increase the number of loads you wash and possibly increase your energy costs.
Faucets, showerheads, dishwashers, and washing machines are only destination points for hot water in your home. The journey of your hot water before it reaches these outlets can be fraught with opportunities for energy losses. Fortunately, you can reduce the incidence of water heat loss from the point of departure to the point of arrival by applying a few basic measures.
Increasing Water-Heating System Efficiency
Reducing hot-water usage is primarily a matter of common sense and exerting a little extra effort to not be wasteful. Once you have applied a few simple, low-cost measures for reducing hot-water consumption, you may want to consider water-heating system improvements if you wish to further reduce your energy bill.
One simple step for reducing water-heating energy costs is lowering the thermostat setting on your water heater. Although some manufacturers set water heaters at 140 degrees F (60 degrees C), 120 degrees F (48.9 degrees C) is satisfactory for most household needs. Furthermore, when heated to 140 degrees F, water can pose a safety hazard (i.e., scalding). For each 10 degrees F (5.6 degrees C) reduction in water temperature, water-heating energy consumption can be reduced 3% to 5%.
If your dishwasher does not have a booster heater, lowering the water-heating temperature is not recommended. Also, many dishwasher detergents are formulated to clean effectively at 140 degrees F and may not perform adequately at lower temperatures. (See previous discussion on Automatic Dishwashers.)
On gas water heaters, thermostats are usually visible. Electric water heaters, on the other hand, may have thermostats positioned behind screw-on plates. As a safety precaution, shut off electric current to the water heater before removing the plates. Keep in mind that electric water heaters may have two thermostats to adjust--one each for the upper and lower heating elements--and adjusting these is tricky. Talk to your local water-heating professional for help with this.
When you plan to be away from home for an extended period of time (at least 3 days), turning the water heater thermostat down to the lowest setting, or even turning the heater off completely, can help you achieve additional savings. Be sure you know how to relight the pilot light on your gas heater, though, before you turn it off.
When you turn on a hot-water faucet during cold weather, it may take several seconds for the water to become hot. This happens because the water travels through pipes from the water heater to the faucet, and some of the pipes may pass through unheated sections of the house, such as the basement. As a result, the hot water loses some of its heat to the surrounding space.
This heat loss can be reduced by insulating hot water pipes wherever they are accessible--especially in unheated areas. Use quality pipe insulation wrap, or neatly tape strips of fiberglass insulation around the pipes. Eventually the water will cool, but it will remain warmer much longer inside insulated pipes.
Insulating your water-heater storage tank is a fairly simple and inexpensive improvement that can help maintain the water temperature at the thermostat setting. Some newer models of water heaters are well insulated and do not need an added layer, but a heater that is warm to the touch needs additional insulation.
Easy-to-install, pre-cut blankets (or jackets) for electric water heaters are widely available and range in cost from $10 to $20. Your local utility company may offer them at a lower price, give you a rebate, or even install them at no cost. When properly installed, a water heater blanket on an electric water heater will pay for itself in energy saved within 1 year. Installation is more difficult on gas- and oil-fired heaters. Ask your local furnace installer for instructions.
If your water heater is at least 7 years old, you should carefully evaluate your water-heating needs and investigate the types of heaters that could replace your current one. Although most water heaters last 10 to 15 years, early investigation and timely replacement can ensure a wiser purchase. For more information on the types of water heaters now available, contact the Energy Efficiency and Renewable Energy Clearinghouse (EREC--see Source List).
Most consumers use more hot water in the evenings and mornings than at other times of the day. For those who have an electric water heater, this usage contributes to the electric utility company's "peak load," or the largest amount of power demand that they have to meet on a daily basis. Some utilities are required to offer their customers "time of use" rates that vary according to the demand on their system. Lower rates may be charged at "off-peak" times and higher rates at "on-peak" times. You may be able to lower your electric bills if you can take advantage of these rate schedules. Check with your local electric utility to find out if it offers time-of-use rates for residential customers, and if so, what the rate schedules are. Some utilities even offer incentives for customers who allow their utility to install control devices that shut off electric water heaters during peak demand periods.
Some ways to save on water-heating bills require greater financial investments than others. You may wish to consider the no- or low-cost options before making large purchases. Also allow for circumstances that may be unique to your household when deciding on the appropriate options (e.g., a small-capacity washing machine could meet the needs of a one-person household efficiently).
Although it is not feasible to eliminate water heating in your home, it is possible to substantially reduce water-heating costs without sacrificing comfort and convenience. The tips in this publication can help decrease your costs for heating water.
| Reducing hot-water usage is primarily a matter of common sense and exerting a little extra effort to not be wasteful. Once you have applied a few simple, low-cost measures for reducing hot-water consumption, you may want to consider water-heating system improvements if you wish to further reduce your energy bill. Lower Your Water Heater Thermostat One simple step for reducing waterheating energy costs is lowering the thermostat setting on your water heater. Although some manufacturers set water heaters at 140°F (60°C), 120°F (48.9°C) is satisfactory for most household needs. Furthermore, when heated to 140°F, water can pose a safety hazard (i.e., scalding). For each 10° F (5.6°C) reduction in water temperature, water-heating energy consumption can be reduced 3% to 5%. If your dishwasher does not have a booster heater, lowering the water-heating temperature is not recommended. Also, many dishwasher detergents are formulated to clean effectively at 140°F and may not perform adequately at lower temperatures. (See previous discussion on Automatic Dishwashers.) On gas water heaters, thermostats are usually visible. Electric water heaters, on the other hand, may have thermostats positioned behind screw-on plates. As a safety precaution, shut off electric current to the water heater before removing the plates. Keep in mind that electric water heaters may have two thermostats to adjust—one each for the upper and lower heating elements —and adjusting these is tricky. Talk to your local water-heating professional for help with this. When you plan to be away from home for an extended period of time (at least 3 days), turning the water heater thermostat down to the lowest setting, or even turning the heater off completely, can help you achieve additional savings. Be sure you know how to relight the pilot light on your gas heater, though, before you turn it off. Unlike dishwashers, washing machines do not require a minimum temperature for optimum cleaning. Setting the thermostat on your water heater to 120°F, which is sufficient for most household needs, is an energy-saving measure you may wish to consider. Install a Timer and Heat Traps Another possibility for electric water heaters is installing a timer that can automatically turn the heater off at night and on in the morning. At a $30 selling price and a do-it-yourself installation, a simple timer may pay for itself in energy saved in about 1 year. More expensive, multisetting timers are also available. Timers for gas water heaters are not as useful or cost effective as those designed for electric water heaters. This is because the pilot light supplies some heat during the night, offsetting some of the energy savings achieved by using the timer. If heat traps were not initially installed with your water heater, adding them is another way of reducing water-heating energy loss. Heat traps, or one-way valves, allow water to flow into the tank and prevent unwanted hot-water flow out of the tank. Heat traps cost about $30, but they may require professional installation, which could be expensive. However, if installed at the same time as a new water heater, heat traps are much more cost effective. Most new water heater models have factory installed traps, saving you the time and expense of installing one yourself. Insulate Hot-Water Pipes and the Storage Tank When you turn on a hot-water faucet during cold weather, it may take several seconds for the water to become hot. This happens because the water travels through pipes from the water heater to the faucet, and some of the pipes may pass through unheated sections of the house, such as the basement. As a result, the hot water loses some of its heat to the surrounding space. This heat loss can be reduced by insulating hot water pipes wherever they are accessible —especially in unheated areas. Use quality pipe insulation wrap, or neatly tape strips of fiberglass insulation around the pipes. Eventually the water will cool, but it will remain warmer much longer inside insulated pipes. Insulating your water-heater storage tank is a fairly simple and inexpensive improvement that can help maintain the water temperature at the thermostat setting. Some newer models of water heaters are well insulated and do not need an added layer, but a heater that is warm to the touch needs additional insulation. Easy-to-install, pre-cut blankets (or jackets) for electric water heaters are widely available and range in cost from $10 to $20. Your local utility company may offer them at a lower price, give you a rebate, or even install them at no cost. When properly installed, a water heater blanket on an electric water heater will pay for itself in energy saved within 1 year. Installation is more difficult on gas- and oil-fired heaters. Ask your local furnace installer for instructions. If your water heater is at least 7 years old, you should carefully evaluate your waterheating needs and investigate the types of heaters that could replace your current one. Although most water heaters last 10 to 15 years, early investigation and timely replacement can ensure a wiser purchase. |
Each year, approximately 3,800 injuries and 34 deaths occur in the home due to scalding from excessively hot tap water. The majority of these accidents involve the elderly and children under the age of five. The U.S. Consumer Product Safety Commission (CPSC) urges all users to lower their water heaters to 120 degrees Fahrenheit. In addition to preventing accidents, this decrease in temperature will conserve energy and save money.
Most adults will suffer third-degree burns if exposed to 150 degree water for two seconds. Burns will also occur with a six-second exposure to 140 degree water or with a thirty second exposure to 130 degree water. Even if the temperature is 120 degrees, a five minute exposure could result in third-degree burns.
Various procedures for lowering water temperature in the home exist, depending on the method of heating. Here are some suggestions:
Electric water heaters. Call your local electric company to adjust the thermostat. Some companies offer this service at no-charge. Hot water should not be used for at least two hours prior to setting. To make the adjustment yourself, start by shutting off current to the water heater, then turn off the circuit breaker to the heater or remove the fuse that serves the heater. Most electric water heaters have two thermostats, both of which must be set to a common temperature for proper operation. To reach these thermostats you must remove the upper and lower access panels. Adjust the thermostat following the instructions provided with the appliance. Hold a candy or meat thermometer under the faucet to check water temperature.
Note: Installation is more difficult on gas and oil-fired heaters. Ask a qualified HVAC contractor for instructions.
1. Cut the tank top insulation to fit around the piping in the top of the tank. Tape the cut section closed after the top has been installed.
2. Fold the corners of the tank top insulation down and tape to the sides of the tank.
3. Position the insulating blanket around the circumference of the tank. For ease of installation, position the blanket so that the ends do not come together over the access panels in the side of the tank. Some tanks have only one access panel.
4. Secure the blanket in place with the belts provided. Position the belts so they do not go over the access panels (Figure 2). Belts should fit snugly over the blanket but not compress it more than 15% to 20% of its thickness. The installation is easier with two people. If working alone, use tape to hold the blanket to the top until you get the belts into position.
5. If your water heater has the temperature/ pressure relief valve and the overflow pipe on the side of the tank instead of on the top, install the blanket so these items are outside of the blanket. Depending on the piping arrangement and location, you may need to compress, or even cut, the blanket.
6. Locate the four corners of the access panel(s). Make an x-shaped cut in the insulating blanket from corner to corner of each access panel.
7. Fold the triangular flaps produced by the cuts underneath the insulating blanket. Repeat steps 6 and 7 for the rating/ instruction plate.
8. The blanket must not be installed on a leaking tank.
Dimensions:
14"w x 24"h x 9"d
Gallons Per Minute:
4.5 (suitable for 2.5 bath home)
Other:
Second can be ran in parallel
Today's buyers are getting savvier to energy savings and the whole green movement in general. When it comes to the speculative market, the most important thing about the Rinnai water heater has less to do with how it operates and more to do with its name. Rinnai is the most recognizable name in on-demand water heaters; this means that when they see Rinnai On-Demand Hot Water Heater in your listing, they go into your home with the mentality that you have put the same "green" concepts into other portions of your project. Aggressive advertising has made sure that nearly every buyer that sees your listing will recognize the Rinnai brand name and what it means to them.
Every potential buyer that can distinguish your home from the countless others that are for sale increases your odds of selling quickly. As the "buzz" over on-demand increases; adding a Rinnai is becoming a relatively low-cost upgrade when you consider all it can do for your listing.
If you would like to discuss the further applications of a Rinnai or anything else, give me a ring @ 360.410.9057
