Tankless on-demand On-Demand Hot Water Heaters

Looking into the matter or tank-less hot water heaters, I have found a number of different manufacturers. A tankless on-demand water heater can be up to 34% more efficient than tank-type heaters. Few people realize that water heaters can be up to 25% of their utility bill. Green Housing and Green Building magazines and websites are promoting the use of tankless on-demand over tank type water heaters.

Tankless on-demand water heaters are also called on-demand water heaters because nothing happens until someone or something (washing machine, dishwasher, etc) turns on the water. Cold water flows into the unit and a sensor activates the burner or heating element. The water flows thru copper coils or a heat exchanger, where it is heated almost instantaneously to the desired temperature. Since there is no tank to fill or empty, the water never runs out. When the cold water valve turns off, the heating components turn off. These type water heaters have been used for a long timer in countries outside of the USA. I remember them in a family home in Guatemala in 1976 and in a hotel in Costa Rica in 1977. Some of the modern units offered in the US even have computer controlled parts and sensors that make it easy to adjust the water temperature. Some tankless on-demand water heaters have remote controls but I cant imagine that being necessary.

Whole house or single point tankless on-demand hot water heater units are available. I think I'd prefer the smaller, single use units. That way if there are problems with the unit, only one bathroom is affected. Might be perfect for hot tubs and the jumbo big bath tubs.

Cost and Durability

Tankless on-demand water heaters can cost more initially than the tank type, but save money and energy in the long run. Recent studies show the tankless on-demand units paying for the extra cost in about 7 years or less. The tankless on-demand type have a projected life of about 20 years....this is far longer than the 5 to 10 years of tank type life. You are not going to have the corrosion and leaking associated with tank type water heaters. Heavy calcified water can shorten the life of a tank less water heater but they can be taken apart and the tubing cleaned of calcium deposit in some cases. Or you can put a whole house water filter in...your family will use a lot less shampoo !

Some people absolutely love them but then there are others... Customers of this type of water heater have said that sometimes the water will go cold in a low flow situation like a handheld shower which requires you to turn off the water and then turn it back on. Most agree that installation is much more difficult than a regular tank type water heater. Some have had problems with the control panels, odd noises, and unresponsive manufacturers customer service dept. After reading the many complaints, it seems clear that it is definitely best to buy your tankless on-demand waterheater from whoever is also the installer so you can get local customer service from someone who cares. Must not flush toilet/fill washer while someone is showering - reduces cold water pressure. Most plumbers don't know how to fix it, and even if they are willing to learn they charge you the hourly rate for their education. Service from the manufacturer's representative can be poor. Parts are expensive. If you use a gas tankless on-demand waterheater, expect to spend a lot of stainless steel venting parts.

The venting that a gas unit requires causes anywhere from a 10 - 20% efficiency reduction from heat escaping out the exhaust pipe. Furthermore, for every cubic foot of gas burned, two cubic feet of air have to be mixed in to create ideal combustion. In a cold climate, this hurts efficiency further. When a gas unit fires, it draws in air around it, heats the water, and then expels warm exhaust outside. Since no house is airtight, this suction action causes a drafting condition where cold air from the outside seeps back in through door cracks and other parts of the house that may not be airtight. By nature of the design, electric units can be nearly 100% efficient; converting 100% of the electrical energy it consumes into heat. All that heat is then transferred to the water - none is lost to the outdoors.

Some suppliers of tankless on-demand, On Demand Water Heaters include:

A.O. Smith - ProStar™ gas water heaters provide a continuous flow of hot water "on-demand" — for both whole-house systems and point-of-use applications that supplement a home’s tank-type water heater. Installation of this water heater may earn you a tax credit up to $300! See their site for a pdf form download. A.O. Smith produced its first water heater in 1936. Their products are Sold exclusively by plumbing wholesalers and plumbing contractors. A. O. Smith is headquartered in Ashland City, Tennessee.  http://www.hotwater.com/products/residential/rg-ondemand.html

Designer Plumbing sells these brands online: Bosch tankless on-demand, Takagi USA, Paloma tankless on-demand, Noritz tankless on-demand and High Efficiency electric from these manufacturers: Powerstar & Ariston, EemaX, Stiebel, Eltron www.designerplumbing.com

Ariston - worldwide distribution of household appliances. The US site is http://www.aristonappliances.us but you may find more information on some of their distributor's websites.

Paloma Water Heaters - Low Energy Systems, Inc., founded in 1977, is a leader in the distribution of the Paloma and other tankless on-demand water heaters as well as a wide variety of gas heating appliances. They will meet any competitive price. They guarantee the lowest price. www.palomawaterheaters.com

Bosch--Gas tankless on-demand Hot Water Heaters - AquaStar - fueled by natural gas or propane (LP). On demand instantaneous water heaters. With some models you can install your Bosch tankless on-demand water heater outside and eliminate the need for costly venting components. With an average life expectancy of more than 20 years, energy savings of up to 50%, and an endless supply of hot water. But not all customers have been happy, read www.epinion.com comments www.boschhotwater.com

Noritz claims to be the number one in the world tankless on-demand water heater manufacturer, not sure what that is based on. Noritz tankless on-demand gas water heaters are designed and manufactured for high efficiency. Using advanced technology allows for 80-85% efficiency in their product. Noritz tankless on-demand gas water heaters provide an endless supply of hot water on demand; only heating the hot water that is needed. This performance cuts water heating costs up to 50%. Noritz America Corporation is a subsidiary of Noritz Japan. Compact in design - about the size of a carry on suitcase for the residential units - the Noritz tankless on-demand water heater allows for installation virtually anywhere, indoors or outdoors. www.noritz.com

Eltron-- A German manufacturer dedicated to producing the highest quality electric tankless on-demand water heaters, thermal solar products, automatic hand dryers, and space heaters available. They have been operating since 1924 in Germany and have been in North America since 1980.The Stiebel Eltron DHC tankless on-demand water heaters are designed for installation at the point of use. They heat water instantaneously as it flows through the unit. Stand-by losses are completely eliminated.Stiebel Eltron has an enviable track record of engineering excellence and product quality. The three years parts warranty is unique in the industry.The Tempra™ has several advantages over a gas-type tankless on-demand water heater. Compared to many similar gas tankless on-demand models the Tempra™ is less expensive to purchase. Installation is also much simpler and cheaper since it is not necessary to vent a Tempra™ to the outside. www.stiebel-eltron-usa.com

Rheem - Expect music in the background here. Rheen says, If your home has 1 bathroom, a Rheem tankless on-demand RTG2-42 series water heater should provide an ample supply of continuous hot water. If your home has 1-2 bathrooms, you should consider a Rheem RTG-53 series water heater. For up to 3 bathroom homes, the larger RTG-74 series water heater should be selected. For homes with more than 3 bathrooms, large volume demands for hot water, or hot water circulating systems, you should choose our GT-199 heavy-duty water heater. www.rheemtankless on-demand.com

Rinnai makes gas units, ...All Rinnai interior units utilize an exclusive cool-to-the-touch vent system that is sealed combustion and requires only one penetration though the roof or sidewall. Rinnai interior units can mount almost anywhere and can have a vent up to 41 feet long. Exterior Rinnai units offer tremendous flexibility and safety. They are mounted on the exterior of your home so they require no floor space. While they are designed to operate to -30° F (-34.4° C), care should be taken to properly install them in colder climates. www.foreverhotwater.com

Seisco - In 1995 DuPont joined David Seitz, the developer of the SEISCO, in his efforts to develop a complete new level of technology for tankless on-demand water heaters for any application. After over 14 years of research and testing, the SEISCO, whose technology has earned its developer 5 separate U.S. and many additional foreign patents. The SEISCO tankless on-demand water heater has earned International recognition. for providing the highest level of temperature control performance, reliability and safety in its operation.

Takagi--The Takagi tankless on-demand Gas Water Heater is the only product of its kind to receive SCAQMD (Southern California Air Quality Management District) approval for it's low emissions (CO, Nox) With high thermal efficiency, Takagi systems use much less fuel than traditional systems. Takagi was begun in Japan in the 1940's and now has US facilities. www.takagi.com

Energy Efficient tankless on-demand Water Heaters Can Save You $300 on Your 2006-2007 Taxes

Thanks to the Energy Policy Act of 2005, passed by Congress and signed into law by President Bush, homeowners who have a gas water heater with an Energy Factor of 0.80 or greater installed in their home in 2006/2007 are eligible for a $300 tax credit on their 2006/2007 income taxes.

One of the primary goals of the Energy Bill, which took effect on January 1, 2006, is to reduce America’s energy consumption. To accomplish this goal, it includes incentives for U.S. consumers to use more energy-efficient products and technologies.

Residential water heating is typically the second largest use of energy in American homes, so the Energy Bill includes a special provision to encourage homeowners to use energy efficient tankless on-demand water heaters like the products listed on this page. This is actually a win-win-win for homeowners, who can now receive a tax credit for purchasing a tankless on-demand water heater which can lead to a reduction of 30%-50% in monthly utility bills while helping to preserve the environment.

Only gas tankless on-demand water heaters with an Energy Factor (EF) of at least 0.80, as certified by the U.S. Department of Energy, qualify for the tax credit. The product line includes sixteen powerful, energy-efficient tankless on-demand water heaters with EF’s above the 0.80 minimum: Ask your plumber for tankless on-demand water heaters. Standard, old-fashioned storage tank heaters have lower Energy Factors because they heat water continuously, whether it is being used or not. “That’s like leaving your car idling in the driveway 24 hours a day,” noted Kyle Murray, Vice President of Marketing for Water Heating. Tankless on-demand water heaters have EF’s as much as 20 points higher than even the best storage tank heaters.

Tax credits are far from the only benefit enjoyed by homeowners who use tankless on-demand water heaters, of course. These water heaters produce an endless flow of hot water, and only heat that water while it is actually being used. The new generation of tankless on-demand water heaters produces flow volumes of almost seven gallons per minute, which is enough for two major simultaneous household uses such as showers, laundry, dish washing, etc. And tankless on-demand water heaters are as environmentally friendly as they are efficient, producing up to 50% fewer greenhouse gas emissions than less efficient storage tank heaters.

Contractors who build energy-efficient new homes or commercial buildings, or who remodel older buildings, are also eligible for tax incentives under the provisions of the new Energy Bill. This tax credit will continue through Dec. 31, 2007. It is possible that the program will be renewed thereafter. A total cap of $500 in credits per individual is allowable under the current law, with additional credits and requirements involved.See also www.energy.gov

The payback period for tankless on-demand water heaters is 3 to 7 years depending on how much hot water you use and the cost of energy. The smaller the amount of hot water that you use, the faster the payoff. If you are single and are seldom at home using hot water, your energy bill reflects the low consumption because tankless on-demand water heaters do not experience standby heat loss. If you live in a warm climate and run air conditioning much of the year you may save more than those who use more heat and any heat loss from the water heater just helps heat the home.

Best Fit Selection is by a tankless on-demand Professional

A tankless on-demand professional generally uses a combination of tankless on-demand technical data and other factors to determine the best fit for their customers. These factors include incoming cold-water temperature, size of gas supply line, and the amount of hot water required during "peak" demand times which vary from home to home. A combination of all these factors is necessary to determine an accurate tankless on-demand selection. People highly recommend professional assistance in the selection and installation whenever possible.

Because most tankless water heater systems are wall-mounted, manufacturer-recommended installation usually meets any seismic codes in earthquake-prone regions without additional bracing or strapping.

According to one manufacturer of electric water heaters: In water heating, there has and never will be a question that the electric water heater is more energy efficient than gas. Since gas prices per unit of heat (Btu) are equal or higher that electricity, electric water heaters, today, can cost less than gas to operate,. Still, in the past, the gas water heater provided more hot water because its higher heating capacity provided much faster recovery. The electric tankless on-demand water heater has breached this gap, and because of its inherently high efficiency has generated a very high level of consumer awareness and interest.

BUT...Not all owners of tankless on-demand hot water heaters are happy. Check www.epinions.com  Home > Home & Garden > Water Heaters and do a search for tankless on-demand. Many here seem to have been do-it-yourself types and used the gas units.

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