Tankless Water Heaters Growing In Popularity, Offer Big Savings - AP

[hatrack]

Americans love their hot water. Lots of it. And while tankless water heaters deliver unquenchable supplies of on-demand hot water, many homeowners are warming to other benefits of these appliances: big energy and water savings.

According to a water heater expert, tankless versions can lop 30 percent to 50 percent off water heating costs compared to traditional water heaters. On-demand heating doesn't waste water by allowing the flow to run until warm enough for use.

"A typical 40-gallon heater is like running your car all night in the garage until you drive it," said Peter LaRose of Nelson and Small, a Northeastern U.S. distributor of top-rated Rinnai tankless heaters. "Why have a water heater running when you don't need it? A tankless system uses no energy until you turn on the faucet."

Tank systems guzzle energy nearly all day to maintain a preset temperature. As water cools, the system kicks on to reheat water. The cycle repeats day and night whether anyone is home or not. And as many morning bathers who are last in line for a shower can attest, a tank water heater often can't keep up with high volume demand for showers, spalike tubs, and whirlpools. LaRose says only about 30 percent of a tank is drawn off before water must be heated again. "It's an illogical way to heat water."

EDIT

Tankless heater maker Rinnai now markets a single unit better suited to American homes and American appetites for hot water. The compact natural gas unit is wall mounted inside or outside a home. Sensors detect when a faucet is turned on, forcing water over a thin copper plate heated by 32 small burners. The unit is vented outside. The compactness of the heater — 18 inches wide by 27 inches high — makes it a space saver. No mechanical room is necessary. Homeowners use digital keypads to preset water temperatures to various rooms. Control pads are typically installed in laundry rooms, master baths, or kitchens. The keypads resolve safety issues too."

EDIT

http://www.enn.com/news/2004-04-13/s_22726.asp

[fairfaxvadem]

1. these things are awesome..

First encountered them at a friend's home in England, where they are basically SOP for many there.

Checked into them when it was time to replace mine, and unfortunately, they are still quite expensive here and I just didn't have the money at the time...

We could learn a lot from the Europeans, but nooooo....

[truthspeaker]

2. I think they're pretty standard in Europe

Makes sense to me. When my tank-style heater dies I'll look into upgrading.

[displacedtexan]

3. Everyone I know in England has one of these.

Currently, I have hot water on demand, as described in the article you cite.
I also have a heat pump, which works beautifully for both heating and cooling the air. In fact, I had a heat pump in Texas (Austin), in Northern Michigan, and now in Baltimore. They work extremely well, monthly electric bill is about $100, and they are much more efficient and cost effective than standard furnace/ac systems.

Standard hot water heaters are explosions waiting to happen. If you don't raise them off the floor, the corrosion that occurs over time can be fatal when the system finally blows up.

[ixion]

4. very, very cool... that makes so much more sense

than our current solution here in the States. Think the utility companies are going to be happy about it? No, sir. Not one bit. :evilgrin:

[qb]

5. I've got one on my list when I can afford to replace our old tank.

No more rusty bathwater!!!

[NMDemDist2]

6. I have one. It's great, but...

a couple things to think of though. The unit itself wasn't that expensive (comparable to a 150 gal conventional tank) but we had to get an electrician out to get enough power to run the two heaters. It works well for my husband and myself but would be a questionable choice for a family. It can only supply one need at a time (ie if someone's taking a shower, you can't do dishes or laundry at the same time)Some of that can be over come with "at the sink" heaters. Also you have to decrease your water pressure coming out of the unit. I am glad of our choice but you must be careful and research if it will fit your family's lifestyle.
edit to add- also you need softwater or the heating elements will fail fast (within 5 years), so check your water's alkilinity when researching your choice.

here's mine http://www.tanklesswaterheatersdirect.com/shop/tanklesswaterheaters/powerstar/powerstarindex.htm

[On the Road]

7. AZDem -- Do They Get Hot Enough?

Glad to hear of your experience.

I have a couple of rental units I might consider these for. Your link said it raised the water temperature 50 degrees farenheit. This might be OK if the water started out at 75 degrees, but if it's 50 degrees that raises it to only 100.

[Bdog]

8. I recommend them to my customers

I recommend that they be used with a solar water heater.

The solar water heaters I recommend have an element in the storage tank so the water temperature is at least 70 before it goes to the thankless heater...even in the middle of winter with no sun the water in the storage tank is 70.

I recommend thankless heaters that have a thermostat control. That way, in the spring, summer, and fall, when the solar water heater is putting out 115 or hotter water the thankless never comes on.

You can cut your hot water energy use by 80% for the year...100% during the summer.