Anyone have a tankless hot water heater??

Should be betwen $200 and $500 dollars depending on the type and size of the system. A vent shouldn't be a problem if your water heater already is powered by gas.

 

I got one afew years ago when I had to do a replacement. I am a single person so demand is not a big issue. The house is very old so I never try to run anything at the same time as the shower. If you have a large family it might be a problem with too many request for hot water at the same time.

Downside: my water has a long distance to travel and the house is NOT well insulated so in the winter the shower tends to be not hot enough. Warm weather is not a problem.

UPSIDE: BIG savings on my gas bill! ps- bought a BOSCH

 

I plan on replacing my current gas heater with a tankless when it goes.

Yes...it is more expensive to buy and install.

But consider.....not only do you save on energy but the tankless should outlast a conventional water heater by several lifespans. I think a tankless can last up to 20 years. In my area a conventional must be replaced every 5-7 years. (That's the cheap Home Depot water heater.)

Now I think if I also install a water softener I might get the tankless to last longer, but I'm not sure. I live in San Diego and we have hard water. I'd love to figure out a way to eliminate the lime/scale/calcium deposits that doesn't cost an arm and a leg.

My relatives in Germany have on demand heaters in the kitchen and the bathrooms. I've been thinking about this ever since I bought my home. I want photovoltaic too but can't afford it.

 

I work for a company that manufactures and sells both tankless and tank-type water heaters. Beware of the marketing claims; you may save money, but much depends on how you use your hot water, where the heater is located, the length of the piping runs, etc.

The tankless style water heaters sometimes have combustion efficiencies around 82%, a bit less than the tank type water heaters. Where they get the energy savings is that you have very little "standby loss" from 40 or 50 gallons of hot water radiating heat out during the day while you are at work, so they will be rated higher under a standard called ASHRAE 90.1. If you have a situation where all your hot water use is concentrated during mornings and evenings, the tankless style can save energy. If you have a usage curve that is more spread out the savings are much less.

However, if you use a large jetted bath tub, want to run two showers at the same time, etc., you will either need a larger tank-type water heater (50 gallon or more) or multiple tankless water heaters. Try to look past the hype in the glossy brochures and look at the recovery rate in gallons per minute (most limit you to 4 or 5 GPM of hot water). Talk to people who own them.

If the tankless style water heater is a condensing appliance, you will save the most. These appliances work by extracting most of the heat out of the flue gasses, causing them to cool, and the water vapor to condense. They can have advertised efficiencies of up to 98%. However, the efficiency is really dependent on the temperature of the water coming into the heater ... in most cases you'll get 95 - 96% out of these appliances. That's 11% higher than the standard tank type water heater ... but they are also thousands more to buy and install. They have combustion air fans, require non-corrosive venting, and require professional installation and maintenance. An achilles heel of heating equipment nowdays is the "hot surface ignitor" which lasts, on average, 2 - 3 years and cost about $150 to replace. An appliance that uses direct spark is a better choice if you want to avoid the frequent replacement cost.

Finally, on venting: the most efficient units will require stainless steel or approved plastic vent. If they are TRULY over 84% efficient, you need a non-corrosive vent material, because as that flue gas cools the condensation that forms is a mild acid, and will corrode through regular metal vents. Corrosion of vent pipes can lead to escaping flue gas, which contains carbon monoxide (CO), an odorless, colorless gas that kills in excess of 200 people a year. Most of the deaths are due to poorly maintained or installed gas burning heaters and water heaters. So don't skimp on the venting material or its installation. Do it exactly as the manufacturer recommends. Your life really does depend on it.

If you are truly seeking the most energy efficient water heater, you cannot beat an electric heater. 100% of the energy consumed by the appliance goes to heat the water, without any heat escaping up or out the flue (they don't even have a flue pipe). While it is the most efficient in terms of energy use, it is also usually more expensive, as electricity is still more expensive than natural gas.

 

Wow, Frank, that was probably the most information I've ever read about hot water heaters that didn't sound like a sales pitch. Thanks for the insight!

Tim

 

We put in a tankless heater (Bosh) about 5 years ago and are very satisfied with it. I did the install myself and had it inspected, not really that hard if you are used to working with this type of stuff. According to my figures, the gas savings paid for the extra cost in about two years. Another thing that we didn't count on was the space savings, it's amazing how much this adds up to when you no longer have that 40 or 50 gallon of water in the basement. All in all, if we ever moved to a new location, a tankless heater would be a requirement.

 

Why would you need a hot water heater? If it's hot water you don't need to heat it!

Sorry couldn't resist.

I thought about installing one, but we are a big family, so it wouldn't be able to keep up.

 

<div class='quotetop'>QUOTE(Godiva @ Jun 21 2006, 10:13 PM) [snapback]275107[/snapback]</div>

We just got a new water heater installed yesterday in San Diego (12-year guarantee). The last one was installed in 1982 so it lasted longer than I expected. I really wanted to get a tankless, but it was too expensive for our budget. Pity, I'm sure it would be a good selling point when you sold your house. We were able to go from a 30 gallon to a 40 gallon, though.

My parents have a water softener and it works well with them. I use the Mr. Clean car wash on the Prius, which has the ionizer. It does seem to require a new cartridge pretty quick.

 

That would make installing a water heater a tankless job.

 

<div class='quotetop'>QUOTE(tcooper185 @ Jun 22 2006, 04:12 AM) [snapback]275164[/snapback]</div>

I head up the Service and Customer Service departments of our division, so I'm a bit more in tune with the things that disappoint customers than sales people are. Its amazing the things people are told by salespeople for the installers (not our guys, but the dealers out there). Honestly, folks, there is no free lunch.

 

<div class='quotetop'>QUOTE(aaf709 @ Jun 22 2006, 10:25 AM) [snapback]275248[/snapback]</div>

I live alone so I don't need to worry about two showers or some other use. My water heater is in a closet in my kitchen so it doesn't need insulation but the space is limited so I couldn't install a 40 gallon even if I wanted.

Installing a water softener won't help my Prius because the water goes directly to the garage from the meter. The only water going to the garage from the house is the hot water for the washer. No way I'm washing the car in hot water.

My water heater went out a few years after I moved into the house. It's an older home and I had to replace that, the water pipes, then the gas pipes, then the roof. Nothing major has happened lately.

I'm sure I'll need a new flue if I install a tankless.

And I would love to have photovoltaic. Maybe I should start buying lottery tickets again.

 

<div class='quotetop'>QUOTE(Godiva @ Jun 22 2006, 10:28 PM) [snapback]275672[/snapback]</div>

The tankless design might be right for you, then! It certainly helps with the space problem. If the closet wall is an outside wall of the house, the new vent kit is not too horribly expensive. A hole is cut in the wall and the vent goes out horizontally ... fast and less expensive. The site has to work with that, of course (there are requirements for the type of vent and how close it can be to windows, etc.) Its when you have to make a long run with the vent pipe that it gets really expensive. On some heaters if you vent vertically you can use standard vent pipe, which is less expensive than the non-corrosive kind.

Many manufacturers have their manuals on line now so you can see what you need to do in terms of installation. What is hard to find is any kind of repair data. Consumer's Reports doesn't report on this kind of thing, as far as I know.

Photovoltaic is hard to do for water heating ... you need a lot of energy to heat up water! Solar water heating does work, but that's with the sun heating the water directly rather than using photovoltaics and then using electricity to heat the water. Darryl has a photovoltaic house (he's "off the grid") and I think he still uses natural gas for water heating (you out there, Darryl?)

 

<div class='quotetop'>QUOTE(mcbrunnhilde @ Jun 23 2006, 09:51 AM) [snapback]275779[/snapback]</div>

No, ours is a power vent that goes through the wall. If I could have the vertical vent would have been nice, but our flue pipe is too small for both the heater and furnace, so I had to go with the power vent.

 

There are some tax credits available for the higher efficiency units that might help. GAMA, the Gas Appliances Manufacturer's Association (and industry trade group) issued this statement with information on the tax credits:

They have directories with the products from all manufacturers, with the official energy efficiency ratings (which may, in some cases, differ from the promotional material the manufacturer puts out).

The document at http://www.gamanet.org/gama/inforesources....E/WH%2080EF.pdf lists the brands and model numbers of qualifying water heaters. Bosch, Rheem-Ruud, Ruud and Richmond all have models listed.

 

<div class='quotetop'>QUOTE(fshagan @ Jun 23 2006, 02:26 AM) [snapback]275696[/snapback]</div>

Yes, the kitchen closet is next to the outside wall. I have a little drain pipe near the bottom that goes through to the outside in case there is a leak. I already have a flue that goes up through the roof. But if necessary something could be put through the wall to the outside. No windows near by. It's close to the kitchen door but I have high ceilings so it could be vented above the door.

I would want the photovoltaic for the entire house's electricity, not to run the water heater. I've already decided solar water isn't for me. I would love to be off the grid but I think the most I can hope for is trying to get my bill as close to zero as I could. I want photovoltaic to reduce my energy consumption on applicances I have that are not run by natural gas: refrigerator, TV, computer, lights.

I've got a gas water heater, dryer, stove and furnace.

Of course, the price of natural gas is going up too. Now what can we look forward to replacing that? Propane? Methane? Other? (and I understand the underground infrastructure for transporting natural gas in the U.S. is in a sorry state and deteriorating at an alarming rate.)

 

I'm pretty sure Darryl is not 'off-grid', but has a tie-in system. So questions of max power draw are moot.

Presuming I setup tie-in PV, I'll put in an electric tankless around the same time.
The only fossil fuel I want to burn is to toast pita.

fshagan, thanks for the very informative post.

 

If you are able to go electric you might consider www.eemaxinc.com. I put their system in my house 17 years ago and have been very satisfied with the results.