Tankless water heaters, also known as demand-type or instantaneous water heaters, provide hot water only as it is needed. They don't produce the standby energy losses associated with storage water heaters, which can save money. Here you'll find basic information about how they work, whether a tankless water heater might be right for your home, and what criteria to use when selecting the right model. Check out the Energy Saver 101: Water Heating infographic to learn if a tankless water heater is right for you, and our #AskEnergySaver discussion on water heating for more answers on efficient water heating.
Tankless water heaters heat water instantaneously without the use of a storage tank. When a hot water faucet is turned on, cold water flows through a heat exchanger in the unit, and either a natural gas burner or an electric element heats the water. As a result, tankless water heaters deliver a constant supply of hot water. You don't need to wait for a storage tank to fill up with enough hot water. However, a tankless water heater's output limits the flow rate.
tankless water heater installation
Tankless water heaters avoid the standby heat losses associated with storage water heaters. However, although gas-fired tankless water heaters tend to have higher flow rates than electric ones, they can waste energy if they have a pilot light. This can sometimes offset the elimination of standby energy losses when compared to a storage water heater. In a gas-fired storage water heater, the pilot light heats the water in the tank so the energy isn't wasted.
The cost of operating a pilot light in a tankless water heater varies from model to model. Review the manufacturer's literature to determine how much gas the pilot light uses for the model you're considering. Look for models that have an intermittent ignition device (IID) instead of a standing pilot light. This device resembles the spark ignition device on some natural gas furnaces and kitchen ranges and ovens.
Proper installation depends on many factors. These factors include fuel type, climate, local building code requirements, and safety issues, especially concerning the combustion of gas-fired water heaters. Therefore, it's best to have a qualified plumbing and heating contractor install your demand water heater. Do the following when selecting a contractor:
If you're determined to install your water heater yourself, first consult the manufacturer. Manufacturers usually have the necessary installation and instruction manuals. Also, contact your city or town for information about obtaining a permit, if necessary, and about local water heater installation codes.
After your demand water heater is properly installed and maintained, try some additional energy-saving options to help lower your water heating bills. Some energy-saving devices and systems are more cost-effective to install with the water heater.
Navien Premium Efficiency condensing tankless water heaters are the #1 selling high efficiency condensing tankless water heaters in North America. The NPE-2 series offers ultra-high efficiency up to 0.96 UEF to keep your utility bills low, endless hot water, and exclusive ComfortFlow technology with a built-in recirculation pump and buffer tank.
It is worth switching to a tankless water heater if you are looking for a more efficient option. Tankless water heaters can save you money on your energy bill, and they can also have a longer lifespan than traditional water heaters.
To choose the right size tankless water heater for your home, you will need to consider a few factors, such as: the number of people in your household, the average water usage in your household, and the climate in your area.
Consumer Reports recently tested four electric and five gas whole-house tankless water heaters from such brands as Bosch, Navien, Noritz, Rheem, Rinnai, Tempra, and Trutankless to see how costs, performance, and energy use stack up against that of conventional storage tank water heaters. We'll walk you through the results and considerations of going tankless.
Switching to tankless from a storage tank water heater is no easy swap because it requires a plumbing retrofit and possibly an upgrade to your electric service or gas lines to increase capacity. Considering that 90 percent of hot water heater installations take place during an emergency, according to the American Council for an Energy-Efficient Economy, that puts you at a disadvantage when you're negotiating with a prospective plumber or contractor to make the switch on your tight timeline.
Because the differences among models were negligible, instead of breaking out individual models for ratings like we do with most other products, our engineers grouped all the gas tankless units together and all the electric tankless models together, and compared the groups with their conventional storage tank models that run on the same fuel. You can see the results in our water heater ratings charts.
Storage tank: Storage tank water heaters typically have a capacity of 30 to 60 gallons, but the most common size is 50 gallons. The capacity you want depends on the size of your household and how much hot water you use (your plumber can help with the calculations). Using natural gas, electricity, fuel oil, or propane, these tanks continuously heat water to keep a full store at the ready. That means you're paying to have hot water whether you need it or not.
Tankless: As their name implies, tankless, or on-demand water heaters, don't store water in a tank. Instead they heat water as it passes through the unit, using a heat exchanger to rapidly bring it up to temperature. (They run on electricity, natural gas, or propane.) Heating water only when you need it eliminates the standby energy losses you get with a storage tank.
Storage tank: Tank style water heaters are less expensive than tankless. We paid $570 (electric) and $600 (gas) for the two 50-gallon Rheem tank water heaters we tested, but we have seen tank water heaters priced for less at home improvement stores. Tanks with larger capacity or energy-efficiency upgrades cost more.
Replacing your old storage tank with a new one of the same capacity is a pretty basic plumbing job, and some homeowners do it themselves. But most manufacturers recommend using a certified plumber, and you may need one because tank water heaters have changed, as noted, to meet tighter energy standards. Depending on what your plumber charges per hour, installation can be $600 to $800 if the existing hookups are compatible.
Storage tank: We included two conventional water heaters in our tests as a control to compare their performance to the tankless units. The gas and the electric storage tank water heaters easily delivered a steady supply of hot water that reached our target temperature of 120 F.
Storage tank: In our tests, we judged the annual energy consumption cost of the conventional water heaters to be Very Good for the gas model and Fair for the electric. Both rate Good for energy efficiency. We calculated that the annual operating cost for a gas model is $245 (based on an average price of $10.86 per 1,000 cubic feet of natural gas) and the yearly cost of running an electric model is $580 (based on an average electricity rate of $0.132 per KWh).
Tankless: Gas and electric tankless water heaters run more efficiently than the conventional water heaters of the same fuel type. We rated the annual energy consumption cost Excellent for a gas model but only Fair for an electric, but both rate Very Good for energy efficiency. Using the same rates above, the annual operating cost is $195 for a gas tankless and $535 for an electric.
Storage tank: Our payback calculations are based on replacing a 50-gallon storage tank water heater with a tankless water heater, then calculating how much the tankless model costs to operate and how much energy it saves. We used the installation of a tank water heater as the benchmark.
Tankless: We factored in an installation cost of $1,250 for a gas tankless and slightly less, $1,150, for an electric. Using a natural gas rate of $10.86 per 1,000 cubic feet, we calculated that the payback time for converting from a storage tank gas water heater to a gas tankless ranges from 22 years to 27 years. For an electric model, assuming energy costs of $0.132 per KWh, the payback time to replace a conventional electric tank with an electric tankless ranges from 12 to 20 years.
Caccia, the third-generation plumber, says that once you make the switch, labor costs are less for replacing an old tankless water heater with a new one than for replacing an old storage tank with a new one. In part that's because removing a large tank takes more time and effort than removing the much smaller tankless units.
Check for rebates. Whether your water heater installation is new or a replacement, you may be eligible for a rebate from your local utility company, which can offset some of the cost. To see whether your utility offers rebates, check its website or the federal Energy Star rebate finder and the Database of State Incentives for Renewables & Efficiency.
Did you know approximately 20% of your home energy use comes from heating water for cooking, dishwashing, bathing, laundry and other daily uses. This can cost the average homeowner over $500 just to run a standard storage water heater.
Tankless water heaters are extremely durable, lasting up to three times longer than traditional tank-type water heaters, and require little maintenance over its lifetime. We want you to feel comfortable with a tankless water heaters so we back them with an extra long extended warranty. Schedule Your Appointment Now The Nature of your issueSelect Plumbing IssueWater HeaterSewer LineWater LineLeaksDrain ClogToiletFaucetGasOtherSelect Date MM slash DD slash YYYY Select Time8:00 AM - 10:00 AM10:00 AM - 12:00 PM1:00 PM - 3:00 PM3:00 PM - 5:00 PMYour Name Your Email* Your PhoneYour Street Address Your Zip Code CAPTCHA 2ff7e9595c
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