Why Tankless, Hybrid Electric, and Solar Water Heaters Just Don't Work!

Tankless- expensive, high maintenance, high failure rates, high install costs, limited flow rates, poor winter performance, long payback.

Hybrid Electric- too tall, need surrounding space for heat exchange, poor durability, noisy, may need condensate pump.

Solar- requires southern exposure, cold & cloudy days: poor performance, very long payback, high install costs

What works?

The good old Storage Tank water heater- electric is OK, fast payback for gas or propane fueled(if low fuel price). Easy to maintain. Best to purchase long warranty unit for maximum durability.

How can this be? The best available technology at a reasonable cost will always prevail. And it has to, in a word, JUST WORK! With the exception, sometimes, of federal government mandated technology, (and dehumidifiers)!

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Comment by Tom DelConte on October 4, 2013 at 3:22pm

Thank you for your insightful comments! Winter's almost here. Still operating 22 year old propane fueled tank water heater. Just payed $1.69/gal for propane in SE Penna. All of my calculations show 20 year payback on all alternatives. Let's just run those tank based units!

Comment by Jack Sadyak on May 14, 2013 at 2:41am

Really valuable information..Great post... Thanks for sharing with us..

Comment by Curt Kinder on January 30, 2013 at 8:40am

Funny how a site hawking tankless heaters insists they are the cat's backside...

Comment by Eric Johnson on January 29, 2013 at 11:10am

Hi Tom, I found a link here: http://water-heater-tankless.com/2010/02/save-energy-by-replacing-y... which presents the pros of tankless water heaters. I hope this will help.

Comment by William H Nickerson on December 30, 2012 at 12:19pm
Comment by Curt Kinder on December 29, 2012 at 2:01pm

CR's advice makes sense for those who have reasonably priced natural gas. All others are well-advised to take a hard look at other options. I'm no fan of tankless, but the high btu cost of propane and electricity (used resistively) compared with NG in nearly all markets makes the Vertex or heat pump water heaters worth extra consideration, particularly in cases of households with 3 or more persons.

I dislike the use of the phrase "up to" as in "up to 30%" The reader tends to forget the "up to" and focus on the proffered numeric value, even when that figure is way high for all but a tiny minority.

Comment by William H Nickerson on December 29, 2012 at 9:27am

I apologize...my wife says that to me all the time... Best wish's for the new year...give my best to the Koke Brothers.

Comment by Tom DelConte on December 29, 2012 at 9:10am

Hello Bill,

Very funny! It's OK to comment, but you should make some veiled attempt at being polite and making sense! BTW, I don't even think about driving to Baltimore to pick up hot or previously used tankless heaters that don't work as claimed anyway. Enjoy your holiday, tom d

Comment by William H Nickerson on December 28, 2012 at 9:58pm

Tom, I just read your post addressed to me....Were you Sara Palins speech writer?...Problems with water sediment...installed cost...and electrical upgrade for the tankless ? The answer to all these is a bigger ele.storage? All your work and you never onced used BTUs or KWHrs ?.. Can you see Russia from your house?  

Comment by Tom DelConte on December 28, 2012 at 5:07pm

To William H Nickerson : just found this, by CR, please feel free to comment:

Heating water accounts for up to 30 percent of the average home's energy budget. Some makers of gas-fired tankless water heaters claim their products can cut your energy costs up to half over regular storage heaters. So is it time to switch?

Probably not. Gas tankless water heaters, which use high-powered burners to quickly heat water as it runs through a heat exchanger, were 22 percent more energy efficient on average than the gas-fired storage-tank models in our tests. That translates into a savings of around $70 to $80 per year, based on 2008 national energy costs. But because they cost much more than storage water heaters, it can take up to 22 years to break even—longer than the 20-year life of many models. Moreover, our online poll of 1,200 readers revealed wide variations in installation costs, energy savings, and satisfaction.

With the help of an outside lab, we pitted Takagi and Noritz gas-fired tankless water heaters against three storage water heaters. We didn't test electric tankless heaters because many can't deliver hot water fast enough to replace a conventional water heater if ground­water is cold. Even in areas with warm groundwater, most homeowners would need to upgrade their electrical service to power a whole-house tankless model.

Our tests simulated daily use of 76 to 78 gallons of hot water. That's the equivalent of taking three showers, washing one laun­dry load, running the dishwasher once (six cycles), and turning on the faucet nine times, for a total of 19 draws. While that's considered heavy use compared with the standard Department of Energy test, we think it more accurately represents an average family's habits. We also ran more than 45,000 gallons of very hard water through a tanked model and a Rinnai tankless model to simulate about 11 years of regular use.

Here's what else we found:

Water runs hot and cold
Manufacturers of tankless water heaters are fond of touting their products' ability to provide an endless amount of hot water. But inconsistent water temperatures were a common complaint among our poll respondents. When you turn on the faucet, tankless models feed in some cold water to gauge how big a temperature rise is needed. If there's cool water lingering in your pipes, you'll receive a momentary "cold-water sandwich" between the old and new hot water. And a tankless water heater's burner might not ignite when you try to get just a trickle of hot water for, say, shaving.

Nor do tankless water heaters deliver hot water instantaneously. It takes time to heat the water to the target temperature, and just like storage water heaters, any cold water in the pipes needs to be pushed out. And tankless models' electric controls mean you'll also lose hot water during a power outage.

Up-front costs are high
The tankless water heaters we tested cost $800 to $1,150, compared with $300 to $480 for the regular storage-tank types. Tankless models need electrical outlets for their fan and electronics, upgraded gas pipes, and a new ventilation system. That can bring average installation costs to $1,200, compared with $300 for storage-tank models.

Tankless units might need more care
During our long-term testing, an indicator on the tankless model warned of scale buildup. We paid $334 for special valves and a plumber to flush out the water heater with vinegar. Many industry pros recommend that tankless models be serviced once a year by a qualified technician. Calcium buildup can decrease efficiency, restrict water flow, and damage tankless models. Experts suggest installing a water softener if your water hardness is above 11 grains per gallon. Ignoring this advice can shorten your warranty.

Efficient storage models are pricey
We also tested the $1,400 Vertex, a high-efficiency storage water heater by A.O. Smith. The manufacturer claims its installation costs are similar to a regular storage model. But its high cost offsets much of the roughly $70 per year the Vertex will save you. Instead, we recommend buying a conventional storage water heater with a 9- or 12-year warranty. In previous tests, we found that those models generally had thicker insulation, bigger burners or larger heating elements, and better corrosion-fighting metal rods called anodes.


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