True, new water tanks do have good insulation, but they still can't compete with a tankless. The two inches of foam surrounding a tank is about R14. The tank is trying to keep a temperature differential of 60 degrees, assuming you want 130 degree water and your tank is in conditioned space at 70 degrees. If you had R14 in your walls and were trying to keep your house at 70 degrees during a 60 degree differential (i.e., when it's 10 degrees outside), you'd say your insulation was insufficient.

In my house, I have an electric tank. 14 years ago, I put it on a timer that turns it off from 11am till 5pm and then from 11pm till 5am. I could immediately notice the difference in my electric bill. As I recall, the timer was expensive ($80), but I easily saved that in a couple years. Unless you spend a day watching your electric or gas meter, it's hard to imagine how much you're wasting by heating water that you won't use.

I just put a demand electric water heater in my shop/garage. It fits between a stud bay, so there's no floor space used. Since I'm keeping track of my building costs (now at about $83 per square foot), there's 6 square feet (or $498 of floor space) that I didn't have to build for a tank heater.

I replaced my tank heater a few years ago (right after the 5 year warranty ran out, of course). What a pain to drag it up a few stairs, use a hand cart to get it into the truck, drive to the dump, where I paid a $20 disposal fee. I figure my time is worth at least $20 an hour, so there's $80 out the window for me. When the tankless goes, I can throw it in the garbage can.

The "net cost" calculations are difficult because it's hard to imagine all of the variables, what with tank and tankless being so different. I'm building again next year and plan to go tankless. It's a get-away place, and since I won't be there all the time, tankless is really a lot cheaper.

Mark

davidandkasie, how often do you even think about your water heater in the course of a week? It sits there doing it's job while you're at work, while you're asleep, cycling on and off without you knowing it. Saying it doesn't cycle very often, based upon how often you happen to notice, is akin to saying your heart doesn't beat very often. Only when you run, right?

I had the misfortune to own a tank heater with the bad habit of blowing out the pilot when the burner would ignite. The next time it needed to cycle, it couldn't because the pilot had been blown out. This forced me to check for a pilot at least twice a day, usually in the morning and again after work. It was always out. This leads me to believe that water heaters turn on and off more frequently than you think.

The other aspect is that nobody needs 120F or 130°F water for a shower. There's no need to heat the water quite that high with a tankless unit. I set mine at 102°F (summer) or 105°F (winter). That's a 55°F differential at 50°F incoming. My incoming temp in summer can reach 75°F to 78°F which is low as a 24°F differential. My shower flow rate is lower than 2.5 GPM. Typically it's about 1.5 GPM. Tankless detractors always throw out extreme numbers. Every usage situation does not fall into those parameters.

FWIW, I checked the gas bill for June and July '04, which was the last two months I had a tank heater. The total was $43.10 In Aug and Sept my gas bill total was $33.64 Since the home isn't heated during those months, the only use of NG was the water heater and cooking. A savings of 22% A nice bonus, but I would have paid an INCREASE of 22% to avoid running out of hot water in the winter.

i have an electric WH. the temp is set to 130. I turned the breaker off to it one day, and 10 hours later water coming from it was still 128. so, no it does not cycle much exscept during use and long periods of non-use. the WH is only 2 years old, and is always cool to the touch. therefore, it is well insulated.

for a gas WH, if it has a standing pilot, there will be continuous minute usage. the ones with an ignitor instead of pilot eliminate this small usage, but add the complication of another electronic component to fail.

hands down, the most reliable and cost effective WH for daily use is a gas unit with a standing pilot.

For those of you searching the forums trying to decide which water heater type is best for you, read this.

Good info. from both sides of the fence. In my situation, there is only the wife & I. We both have careers, for which, I have to travel 60% of the time. The nat. gas tank heater I have is getting less efficent. I've owned the house for 11 yrs., don't know how old the heater is. I think the situation is great for a tankless heater. With rebates, great deal in the long haul. Only question is output size, I my have to consider in relation to sale of the house in the future

Actually Lazypup made a very good point.

Now a tankless unit does not burn any gas when not in use but it can burn large amounts of gas when in use depending on the demand at that time. Newer tankless units only burn the amount of fuel needed to meet the temp. setting for the amount of water running through them. In other words it will use less gas to heat water for one faucet than it will to heat water for two showers. So the actual gas usage of a tankless is variable.

The tank type unit uses fuel to maintain the water temp. during the day while it's not in use and to heat the cold water coming in while in use. The length of time the burner will run is dependant upon how much water is transfered. Same as tankless...less gas to recover from one faucet than two showers, so it's usage is also variable.

When making the decision to install a tankless unit do not use fuel savings as a selling point, there may or may not be one. In fact a tankless unit can cost more to operate under some circumstances....such as: "The water stays hot forever so I take longer showers", or " I can run the washer, dish washer, and take a shower all at the same time". Which means full flow and full btu demand for the unit which means lots of gas burned, more than a tank unit.

The decision makers for tankless should be:
Can I use the saved space?
Do I want unlimited hot water?
Am I willing to pay the extra price for the unit and the installation to get it, knowing I probably won't save any money on the gas.

A tankless unit can cut gas bills, but it's not really expected but is pushed by the salesmen and the manufacturers. Any honest tech., installer, plumber, slaesman will tell you that may not be the case. Many people have installed tankless only to find their gas bills go up, but some do save. I think the truth always lies in the middle so expect it to be about the same.

A quick report of some real-world numbers: After my shower tonight, I left the water running so I could check the reported parameters on my electric tankless. We're having a "Central South Texas Cold Snap" at the moment, with a low of 31°F last night, and 41°F now. Yes, I know, that doesn't compare to Minnesota for example, but I'm not trying to compare to that, just reporting what I have here.

Input temperature: 67°F
Flow Rate: 1 GPM
Output Setting: 102°F
Temperature Rise: 35°F
Temperature Measured At Bathtub Faucet with Instant-Read Kitchen Thermometer: 98°F (warm enough for me)
Tankless Output Capacity: 18% of maximum
Tankless Current Draw: estimated 5,184 watts or 21.6 amps @ 240 volts ... about the same as my heat pump

The duration of that shower, which normally wouldn't include the extra time with the water running, is all the hot water I used for the entire day.

Dadoes has just posted the information that proves my point. In the sunbelt a tankless performs fine but they do not perform well in colder northern climates.

Notice that he is in S.Texas and even with a winter cold snap the ground temperature of the incoming cold water is still 67degF. By contrast, here in Pennsylvania where I currently live the summer cold water temperature is in a range of 50 to 55degF and dropping to 35 to 40degF in mid winter.

With his tankless set for an output setting of 102degF his unit must heat 100% of the water supplied to the shower although that claim of 1gpm sounds incorrect when we consider that a shower is rated at 2.5gpm, but this is also possible if he is taking a relatively cool shower.

We have 5 adults in my household and three bathrooms so the design parameters of my system was to have sufficient hot water for three people to simultaneously take a 10 minute shower.

Allowing that a shower is rated at 2.5gpm I then needed a water heater that could provide 7.5gpm. The only Rinnai Tankless that could provide 7.5gpm @ 55deg diffenential was the Rinnai R-85E at a retail cost of $1,748 plus installation. (Fortunately I am a plumber so installation is not an issue for me).

Now for the expense that no one seems to consider. If I use a tank type water heater I only needed a 1-1/4" gas supply line with a permit and connection fee of $750 however if I opted for the tankless(237K/BTU) I would then need to increase the gas line to 2" and the permit and connection fee for a 2" line would have been $1400 not to mention that increasing to 2" nearly doubled the material cost for pipe and fittings.

The tankless would also mean that i could not install a recirculating loop unless i installed a holding tank.

Instead of the tankless I opted for a U.S.Craftmaster(Div. of A.O.Smith) FG1F5050T4NOV 50gal gas tank type water heater , initial cost $336 at a local hardware store. To that I added a whole house tempering valve at a cost of $48.

This water heater has a 1st hour recovery rate of 50gal at an output temperature 10degF below the thermostat setting.

The tank thermostat is set at 180 and the tempering valve output is set at 110 which means that in order to supply 110degF water the tempering valve mixes 60% hot water from the tank and 40% cold water. This means that although the water heater only produces 50gal of hot water it effectively produces nearly 90gal of hot water at my demand temperature of 110degF thus we have absolutely no problem simultaneously supplying three 10 minute showers.

This also means that by selecting the tank type instead of the tankless I saved $1400 on the cost of my water heater and nearly $1000 on the cost of my gas line (tie in fee + material) and i also enjoy a nearly endless supply of hot water.

Again LazyPup makes a very good honest point.

Fact: I installed a tankless unit for a customer last year, A rinnai outdoor unit. Total installation cost for new gas line, new water lines to unit, new wiring to unit: $2500. This customer could have removed his old electric unit and installed a new one by himself easily for around $300-$400 I guess. So he now has about $2100 extra in a water heater, $2100 he'll never recoup, ever. Noiw way that unit(and rinnai is a good unit) will last long enough. So for $2100 he gets unlimited hot water as long as he has power and gas, is it worth it? Not to me.

I could have installed one for myself when I was building my hopuse but I did not. The unit would have cost me about $800 and my electric tank heater was only about $260. I saved on my gas piping costs too so lets say about $600 total saved. Even at $600 I don't think I could make it back any time soon. Now if I could get a scratch and dent tankless unit at a trade show for very little $, I might do it. I know a man that uses two Rinnai's to heat his water and supply hot water to an air handler for his HVAC system. He uses about 500 gallons a year to do this so thats about $945 @ 1.89/gallon propane. Plus his light bill(don't know how much this is but I guess around $80-$125/ month. So lets say thats about $1900/year. His house is the same sq.ft. as mine. I use about 100 gallons of gas a year, thats roughly $189. My light bill is about $145 month, roughly $1900/year. So the $600 extra to install the tankless would never be recouped. Now compare that to say $2100 extra for all retail pricing. So agin if the extra $ needed for the installation is worth it to have unlimited hot water, then a tankless is right for you.

1 GPM is correct, as reported by the tankless unit's status screen (I suppose it could be wrong). Only hot water running at the shower. I don't turn the faucet to full-on, no need to do that.

About $3.00 a month to keep hot water sitting in my 40 gal natural gas, over 16 year old water heater.
Read the following which I posted in another thread.
I figured $40 or less to keep the water heated in my situation.
How many years is it gonna take at $40 per year to pay for the excess cost of a demand heater....
Anyway, read what I wrote previously...
----------------------------------------------------------
Oct 17, 2006
It seems much of the problem in this discussion is that very few of the posters have a good estimate on how much gas a tankless water heater uses when just sitting there.

My home situation is such that I have it as isolated as anyone can, short of not having anyone living in the house.
I have come to the conclusion that tank water heaters use very very little gas just to keep the water heated.

I use only 5 to 8 therms per month (natural gas).
I have a 16 year old 40 gallon water heater that sits in the basement of a San Francisco Bay Area home where the climate is moderate......winter and summer.
I use very little hot water compared to most people.
Only I live in the house.
Here is my weekly usage.......
1 shower daily (about 10 minutes)
approx. 2 dishwasher loads per week

Thats about it....(I do 95% cold water clothes washing and during the winter months I use about 20 minutes of clothes dryer use per week......just to size/fluff up a few damp items after mostly air drying them)

Importantly, I keep my water temperature low. The temperature is such that I take 100% hot water in my showers. Only on some occasions is it too hot.....and even then only a bit hot. Seldom, almost never too cool.

OK......so you can see, I have about minimal usage, and I suspect that about half the therms used go for my actual personal usage and about half to keep the water heated in the tank 24/7... I never turn the heater off or down.

So with the average therms per month being maximum of 7 therms per month (probably about 6.5 therms average)
If 50% of those are for usage and 50% are for keeping that tank heated and therms cost me about $1.00..........
then it would seem that it only costs about $3.50 per month to keep the water heated 24 hours per day....at my lower temperature setting.

Remember, this is a 16 or 17 year old water heater. Just a regular model.......no super insulated model or anything.
It does have a water heater blanket around it.

I'm guessing that 3.5 therms per month to keep the water heated is far less than any posters suspect ( assuming the other 3.5 therms are for my actual usage requireing more heating vs just letting the tank sit unused)

My usage is abnormal to be sure, but it gives some idea about what the tanks use to keep water warm.
Makes me think the claims of the tankless water heater avdocates are way over the top....exaggerations of how much less gas is used......or conserved.

I'm told that modern water heaters are even more energy saving than my old one.
Seems like real concerns about the environment should be spent in some other energy savings ideas.
When you consider the costs for the tankless water heaters, it sure seems like it will take decades to get any savings, and that only if you don't count the interest you could have made by putting the extra hundreds of dollars in the bank.
I'm thinking it only cost me about $40 per year to keep the water just sitting there heated and about $40 for the incremental hot water I use.

I just heard a radio program yesterday where the guest speaker was from Rinnai America--I think he was president of Rinnai America or something like that, I didn't quite catch his title. Anyway, in Chicago, on Saturday mornings there is a radio show where people call in with their home improvement questions, hosted by Lou Manfredini. He's written books, and writes various newspaper columns, and appears on NBC's Today Show. Mr. Manfredidi is a big fan of tankless.

So, his guest is this guy from Rinnai, and they talk for a while about the advantages to the tankless systems. They answer calls, and the first call is from a lady with a tankless who has had nothing but trouble from her tankless which I think embarrassed the Rinnai guy, but it was live radio, so what could he do. He felt her issue was improper venting, and then he talked with great emphasis about the importance of proper venting and properly-sized gas lines for tankless. Then he went on to say--and remember this is the rep from Rinnai--that one shouldn't choose a tankless if you think it will save you money, particularly in a climate like Chicago's. It should be chosen because you want instant and endless hot water, but not because you hope to save money. He said that the listeners should be aware that incoming ground water during Chicago winters is between 40 and 50 degrees, which puts a large demand on the heater and will use a lot of gas. He added that in a climate like Chicago's, it is important to size the tankless large enough to account for incoming water temperature in the winter.

To close the interview, Mr. Manfredini asked if there was a possiblility in the near future of the upfront costs of tankless coming down, since he felt more people would buy tankless if they weren't put off when comparing those upfront costs to traditional tank water heaters. The Rinnai guy said not in the near future.

By the time he talked about the high upfront costs, the importance of finding a plumber who was knowledgeable about installing the venting and gas lines, and the high gas usage for my climate, I think he must have turned off his entire listening audience.

Tankless may be cost effective after several years if you live in a southern climate. But half the country doesn't.

I just wanted to add one more point to my previous message. That is that I was very impressed with the Rinnai guy--his honesty and frankness, his in-depth knowledge, his pride in his company, his pride in its employees, and his absolute belief in the quality of the products his company makes. You hardly ever see that anymore. After listening to him, I'd choose any other Rinnai product in a minute....just not a tankless.

Instant and endless hot water.....priceless!
I'm going with tankless, but I'm in the half that is in the South.

I checked again this evening when running water at the kitchen sink to handwash a couple cookie sheets. Input temp was 54°F. Output temp 102°F. Flow rate was 0.5 GPM. Sorry, I don't recall the output capacity for sure, but it was a single-digit number, 5% or 8% of maximum I think.

The claim of instant hot water is a lie. No matter whether it is tankless or tank type you have the lead time required to get the water from the water heater to the point of demand unless you install a circulation loop, and you cannot install a loop on a tankless sytem unless you install a small tank type with it.

Lazypup - I agree with you, although in the case of the Rinnai guy that I heard on the radio, I believe he used the word "instant" in the context of comparing it to a tank where if you've used up all the hot water, you have to wait for the water in the tank to heat up again. With tankless, there would not be that kind of wait, although of course you would have the time it takes for the hot water to travel to your faucet/showerhead.

I have my traditional tank sized properly for my household. Consequently, I've never yet run out of hot water, and am perplexed by people wanting to spend several thousand on tankless, and put in a new vent and gas line, so that they won't run out of hot water. But, I don't have teenagers in the house either with their endless showers....

As you can see by now, I got my earlier posted info directly from a 1st rate rinnai tech at a rinnai school.

I have said for a long time: If rinnai makes a product, it's better than anyone else's. I love rinnai products and their excellent tech support.

And, as lazypup stated, there really is no such thing as instant hot water without a circulation loop.

Before I got into the Plumbing trade I was an HVAC tech then licensed as a Boiler Operator. During that time I worked as an operating engineer in a public school system and a major hotel /conference center. If I learned nothing else from those experiences I learned that it is easy to heat water in great quantities in a very short time, however it is very difficult to move that heated water over a great distance and still retain the heat.

Most homeowners could not even imagine the type of equipment required to supply hot wate to a high school gymnasium where 100 kids hit the showers ever 45 minutes and you have 60 showers running simultaniously (24 boys locker room & 36 in girls locker room) or try to imagine what it take in a motel confernce center. over 1500 registered guests all leaving there daytime functions at 5pm and heading to the room to get dressed for dinner. 600 guest rooms all hitting the showers in approximately an hour and you may rest assured that if any single individual in that group gets a cold shower and calls the manager the operating engineer may very well find himself or herself looking for a job. This is not to mention that over half of those guests are running back and forth to their cars, doors standing wide open while while its zero degrees outdoors and your trying to heat the building with the same boilers you heat the water with, and oh, by the way, the kitchen needs steam to keep those 1500 gourmet meals hot as they make their final preparations. Suddenly it begins to snow and you must divert steam to the heated sidewalks to melt the snow. You get everything set up an running just fine, then you go out and drive the snow plow to clear the parking lots and you get a call on your radio, the front desk is telling you the boiler flame out alarm just went off. You race around to the loading dock, park the pickup and run inside and down three flights of stairs to the boiler room 24 feet below. You have 5 minutes to get the bad boiler shut down and a backup boiler up and firing on full fire or you will loose steam pressure. Dozens of valves on the steam header to be changed, condensate pumps to be started and once the rush is over you must immediately determine what caused the failure and begin correcting it because you have 3 boilers but you require a minimum of two. With one offline you have no margin for error, no backup if one of the other two has a problem. If you do nothing else, you must keep the steam up 24/7/365.

When I first went into the plumbing apprenticeship they found out what my background was and I was immediately assigned on a commercial plumbing crew. Schools, hospitals, motels, hotels, shopping malls, laundromats, apartment complexes etc. I had no problem at all with that, but later when my apprenticeship required I get my necessary hours in residential plumbing I felt like a fish out of water.

Suzy Homemaker is telling me she needs an endless supply of hot water so she can fill her 75 gal soaker tub twice a week. Well folks, I realize this may be hard for some to understand and it is surely contrary to what the tankless industry would like you to believe, but filling a soaker tub is not an endless supply of hot water. Running all the showers in your house, plus the laundry, dishwasher, and all sinks while filling that tub is an endless supply of hot water, anything less is a limited supply of hot water. How limited is then dependant upon what type of water heating equipment you have.

When I am asked to design a water heating system for residential new construction I work out the conventional state of the art residential water heating system, then I work out the alternative that will provide a limitless supply to meet the needs of all hot water fixtures in the house simultaneously.

How can this be achieved you ask? With the single exception of showers most hot water demands in a residential structure are small volume and relatively low frequency demands. Rather than run a hot water line to a kitchen, laundry or half bath run a single cold water line and install a small "point of use" type tankless. In some instances the savings in pipe, fittings and installation labor will offset the cost of the small tankless unit. I then design a tank type unit with a whole house tempering valve and a second hour recovery rate that can meet the demand for the showers. IN this configuration generally a 60gal tank type firing at 160degF will supply a continous supply of 110degF water to three showers simultaneously and no matter how many times they start the dishwasher or laundry it has absolutely no effect on the showers.

The problem is, no one seems to want to think outside the box anymore.

The initial price is another variable in whether you'll be happy. I'm surprised at the $1,000-2,000 price tag some are claiming for gas heaters. Both of my whole-house electrics were bought off Ebay for under $500. I'm surprised gas is so much more expensive. Seems like they'd be a simpler design. With electric, you'll have an additional $50 for wire and $50 for fuses, assuming you have room in your panel. I went with a fancy distribution manifold for one install ($100). Compared to lugging a tank around on a dolly, it's almost a wash for me as between the electric tank and tankless.

Mark

Our house (Calif.) has 2 water heaters. Both were replaced in 1995. One serves the master bathroom and kitchen, the other serves the laundry room and 2 full bathrooms. Dec. 2005 one heaters rusted out and started leaking. We chose to replace it with a 50 gal. Rheem unit. The bill included the heater, installation, permits and code upgrades. It came to $1149.

Now the second heater is leaking. We are considering having a tankless installed. The Rheem RTG-74 is $999 on line. I'm not sure how much more it would be locally. Right now the Fed. government is offering a $300 tax credit for putting in a tankless unit. Plus, our local utilities company is offering a $300 rebate (PG&E also is offering $300 rebate). So, that's $600 off the price. I'm not sure what installation, code upgrades and permits will add to the price.

Anyone know what is the quality like on the Rheem tankless units? With $600 in incentives, does it make sense to go tankless?

Katy

Dang, if only I didn't have a conscience, I could buy some really bad plaid sports jackets, hire an ex-stripper, and make a $$ killing selling tankless WHs... leaving the used car and timeshares markets to the other guys in bad-plaid... with their cleavage-intensive receptionists... who can't type. ;')

What started out as a niche product for old rich guys who wanted showers with their trophy wives to last as long as the Viagra, has now almost become mainstream, against all logic, data, and spreadsheet projections of total cost of ownership (TCO)... too funny!

And the REBATES situation, is proof that gov't growth and lobbyist corruption is way out of control.

OTOH, think about this angle: Why would the utility give you a rebate, unless they were fairly sure you were going to use MORE gas/electricity, i.e a loss-leader? (Is the rebate dependent on having teenage girls in the house?... lol! )

PS: Better make sure that utility rebate is NOT them passing through the Fed.gov rebate, i.e. verify you really get $600, not just $300.

Lazypup, you are still the Supreme Master Plumber of the Great White North!... or of this forum, whichever pays more, lol.

Seriously, what brands/models of residential WHs can be set to output @ 180 degrees? The few "civilian" WHs I've installed, adjusted, or tossed in the trash, all seem to top out at 150F...?

As for Lazypup's math above, the only error I spied, on cursory glance, was that he used real world gasflow/BTU data for the tankless, but assumed 100% theoretical efficiency for the conventional unit.

There are flue losses, plus you have to heat the metal, ceramic, and other materials surrounding the water, but even here I'm confident that the smaller flue, tall rise, and refined burner design of the tanked WH yield better efficiency in terms of cu. ft. of gas consumed per gallon of H2O heated per degree F. (Don't forget, the pilot flame is not "wasted" gas, as almost all its heat goes into the water.) I'm sure A.O. Smith could provide the real-world numbers.

... did your original thread, on this endless debate, finally exceed the maximum storage limit of the THS/Gardenweb servers? I know at one point I had to install Firefox browser, because MS-Exploder could no longer load that entire thread without crashing... LMAO!

That thread was a screamer! Way more irrational than this one.

You gotta figure a way to get royalties from all "tankless" threads, lol.

The $300 rebate from the Utilities is genuine. I live in Palo Alto, CA. and the utilities are owned by the city. They encourage conservation and recycling. They also have a rebate for putting photo voltaic on your roof, buying energy star appliances, water conserving appliances and right now are offering Free Refrigerator Recycling Plus a $35 Rebate. The statement below is from their web site:

"That old refrigerator or freezer in your garage or basement uses up to three times as much energy as newer models. Let us pick up your older working refrigerator for FREE and make sure these high energy users are taken out of service permanently. This program will insure the proper recycling of more then 90% of the refrigerator components."

So you see, our utility company actually encourages us to use less because it's not some large utility company.

The Fed. incentive is a tax deduction taken off the 2007 tax forms. You have to itemize in order to get it.

Katy

Ahh... Palo Alto, home of Stanford U... you'd think those brainiacs would inform the local utility about the phantom "conservation", LANDFILL costs, total cost of ownership, total ENERGY expenditure, etc.

Do you have a link to your utility's website?

The recycling (and presumably responsible disposal) of older refrigerators SOUNDS good, but $35 won't buy you a new one, it takes mondo ENERGY to recycle/decontaminate/dispose of the old fridge, not to mention the ENERGY req'd to mfr. the NEW fridge (steel furnace, plastic molding, etc.). Has anyone in academia really run the spreadsheet on BOTH sides of the equation?

The newer models seem to last about 10-14 years, the old "evil" ones seem to last 30-40 years! At this point I'm lacking insight, investigation, and HARD DATA, but that's a lot of energy to crank out those 2 or 3 extra units you're going to need, before they are ever plugged in. Could the Appliance Mfrs. Lobby possibly be behind this? ;')

(My extended family has an especially evil fridge up in PA... with the "child-killer" door latch, rounded post-war styling, and these cool semi-circular swing-out shelves... and it's STILL RUNNING fine... OVER 50 years old! Might even be a late 1940s model!... will find out... )

OOPS!... thread hijack!... I'm evil.

Yep, the link is below. The disposal of old refrigerators was to encourage people to reconsider the "second" refrigerator sitting in the garage. You are right, $35 won't buy a new frig. The incentive from the city is to reduce energy usage. And if you do need a new refrigerator, if you get an energy star compliant one, you get a $100 rebate.

While it's true an older model may work, it's usually not as efficient as the newer ones.

Katy

After reading all the commentary on tankless water heaters I think I have found the answer to my question. Thanks guys!

I earlier thought I posted on here but I am such a newbie that perhaps I did it wrong or it went just to lazypup. Anyway, I am at my wits end re: HW heating. We are in Michigan. Usually it is just the two of us--albeit we have a whirlpool tub, double steam shower, laundry, kitchen, etc, etc. A few times a year, however, we have our 5 children, spouses and 11 and counting grandchildren stop in. On Dec. 5, lazypup gave a great explanation of a difficult HW situation he handled. Mine doesn't compare but we are SO confused as to what to do for HW. Architect says--go tankless at least to the Master Bath and laundry. Do Gas HW heater for the rest of the 3 bedrooms (which includes 3 showers and 1 whirlpool and 1 regular tub). Plumber says just go with Gas HW heaters--two of them in series. HVAC guy says add a Super Stor 60 gal for indirect HW heating off of our boiler (but we would have to run the boiler all year). SO CONFUSED. Please help. We are living in this remodel--current HW heater is electric and has blown one coil or whatever its called and so until we figure out the HW situation, we are taking quickie showers. I hate remodeling.....

ktmast, Rheem's tankless are good units. $1000 is a decent price.

lazypup is a dedicated tankless hater. I am a dedicated tankless lover. So I'll pose the question. If two opinions of infinite mass collide on the internet will anyone care? lol

Tankless hot water is the future. I've had white knuckled arguments with many plumbers about tank vs. tankless but in the end most all eventually admit that they know deep down the world is going tankless in a big way. The space you save using tankless is no small consideration. There is real energy savings vs. tanks. Look at the numbers. Look at the BTUs and the water temperatures. Gas and propane powered tankless users save energy on a gallon per gallon basis. That is a FACT. If you heat 100 gallons of 40º water to 140º in a Rheem 40gal tank water heater it will require 1.3 therms of gas. If you heat 100gal of 40º water to 100º in a tankless water heater it will require less than 1 therm. At my home a therm of natural gas costs $1.21. At that rate the actual dollar savings is $0.37. Those are the facts using manufacturer data and the laws of thermodynamics and heat transfer. No anecdotal before and after stories. Just raw data. If somebody wants to shower for an hour that's not the water heater's fault.

Many people believe tankless is not viable in cold climates but consider this. If you heat 100 gallons of 60º water in a tank to 140º it will require 1 therm of energy. Using a tankless to do the same thing will require 0.8 therms. If a therm costs $1.21 you will save $0.20. Your actual dollar savings in energy usage will be 17 cents less in a warm climate than in a cold climate. You save more energy on a gallon per gallon basis in the cold. Does it still not make sense to use tankless in the North?

A BTU is a BTU, a pound is a pound, and a degree Fahrenheit is a degree Fahrenheit. These are physical and mathematical constants. When you plug these numbers into a device that is 84% efficient and compare it to a device that is only 64% efficient(at best) you will always, always, ALWAYS save energy. The only way to deny that fact is by using anecdotes and obfuscation. Moose of Physics out front should have told you. :pokes lazypup with stick:

Go with the indirect off your boiler if your boiler is a newer super efficient one. In the summer, your boiler will only kick on when your tank calls for heat. So it will not run all night and in many houses all day after the morning showers. They dont have their own stacks, so they have no stack losses like tank heaters and only lose like .4 to .5 degrees per hour. If the water was 140 when you went to bed, it will be 136 when you get up. Plenty hot and the boiler will not have kicked on all night. You get the best of both worlds, super efficient boiler (up to 98%) heating your water and a tank that only loses a little bit to jacket losses (and even those are typically into conditioned space). On top of all that, there are virtually no parts to break compared to either a tankless or a tank heater, its just a big tank with a hot water coil in it and a thermostat.
Sized properly, you will not run out of water either, the recovery rate is amazing.

Sorry,

my prior post above was supposed to be addressed to wldsyd's question a couple posts up, but I guess it could also apply to the OP too.

They really need an edit function on this site...

"A BTU is a BTU, a pound is a pound, and a degree Fahrenheit is a degree Fahrenheit. These are physical and mathematical constants. When you plug these numbers into a device that is 84% efficient and compare it to a device that is only 64% efficient(at best) you will always, always, ALWAYS save energy."
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While this is true, and there are benefits to instant hot water, it's a total cost of ownership issue. I'm guessing the average cost of having a tankless installed is $3,500 (at least in my area). Now, how long is it going to take to recoup that cost. Probably longer than the life of the water heater. Theoretically, tankless should last longer than a tank. So lets assume 15 years for the tankless and 10 for the tank. Playing the average Joe, the tankless will cost, on average, ~$3,500 installed. The tank will cost I personally am switing from an electric tank to a gas tank. I think that will save me money and give me a good recovery rate. When that dies, if the tankless are proven and perfected, I'll go that route.

I'm happy with the home I live in and plan to stay here, so I tend to look farther ahead than most people. I plan to buy another heater to have in reserve when my current tankless gets near the end of it's life expectancy. It would take no more than ten minutes to swap out units, and I won't need to call anyone. At one point in the installation of our current unit I turned to my wife and said "Honey, will you bring in the new heater from the garage?" My 120 lb. wife returned a minute later holding the tankless unit. Compare that to two friends helping me wrestle the 50 gal. tank out of the house earlier.

This independence is comforting to have since Murphy's Law dictates your old heater will fail on a three day weekend and you have a house full of company.

I can't tell you exactly how much I have decreased my electrical bill by using the SETS Systems tankless hot water heater (same used at 911 ground zero), but I can tell you that we left the gas pilot light on at my dad's home (he recently passed away). With no one home using the shower or hot water taps (shut off for kitchen remodeling) the gas charge for actual usage was $10.16. This reflects a brand new 40 gallon hot water tank. This does not include the $8.25 gas delivery charge everybody gets.

Temperatures have been above normal in western Washington of late. However, the $10 plus is an actual usage figure.

With my tankless, I need to get the setting correct. Am going to do that before the week is out. Will check inlet/outlet temps, etc. Plumbers never did that with the installation and it's been a little spotty. However, my wife has more difficulty with it than I do. I like the fact that the meter doesn't run except when the unit is on.

I have a friend/business colleague who is a retired high-level Boeing engineer who has had the power company out at his place no less than six times wondering he is using so much less electricity than anyonje else. I think he uses a BOSC electric tankless. It is electric at any rate if that isnb't the right manufacturer.

I also likes SETS customer support (real person on the phone immediately) and lifetime guarantee. My nit cost $822 shipped to my doorstep. Installation was included in the price of the new house. Think it cost me about $400 more for higher higher electrical panel service. Everything else was no extra with my builder.

That's been my experience.

There are so many posts and technical information.

Bottom Line: is it beneficial to get one today if you live in a hot climate like Texas?

Bottom line is, define beneficial.

Do you want loads of hot water, extra-long showers, and being able to run several things at once, with no wait time afterward, then yes.

If you want to save money money and see a significant return on investment in monetary terms, probably not. Tankless units with their expensive installations and yearly maintenance costs, ESPECIALLY if you are on hard water like alot of Texas is, means that you will wait a looong time to see a 100% return, especially with the energy rebate gone this year.

Here are the real-world data. I am a Mechanical Engineer and sort of a dork too I guess. When I was considering the purchase of a tankless water heater I looked high and low for real evidence that it actually lowered utility bills. All I was able to find was anecdotal evidence and people spouting out assumptions with little real data to back it up. So I decided to put one in and track my utility bills and publish the data to set the record straight for others. I removed a traditional tank style electric water heater and installed a natural gas tankless water heater in November 2007. I selected the Rheem RTG-53PVN (Poloma at Home Depot) and purchased it through Lake County Pipe on the internet. I had to install a new gas line to supply adequate gas flow and rework the old venting from the traditional gas water heater that had been there at one time. Before installing this water heater, the only appliance in the house using gas was the furnace so it will be easy to see what the new water heater alone costs to operate during the summer. It is not easy to see what the electric water heater was costing to operate since I did not have access to a watt-hour meter, or any other datalogger to track it's consumption. So I made a spreadsheet listing electric and gas bill data from the time I purchased my house in October 2003 to the present and tried to assemble the data as fairly as possible. Excluding administrative fees tacked onto the bill and basing this analysis only on a cost per kWh and cost per MCF gas basis, compared to the average sum spent on electricity and gas for each respective month from the time I purchased the house (based on this months gas and electric rates), I saved $25.70 in December 07, $12.71 in January 08, $47.78 in February 08, and $36.49 in March 2008. So far it is looking like a very wise purchase since at that rate it will pay for itself in 2 years or less, nevermind the fact that the electric water heater was 12 years old and would have needed replacement soon anyway. That money will now be freed up to save energy in other ways. It works very well and the only complaint I have is that you must have a certain amount of flow before it will turn on and we have a bathroom at the other end of the house that cannot receive enough flow through the sink faucet to turn it on. That problem can be attributed to poor piping and fixed by changing the plumbing or installing a point of use water heater there, but we don't use hot water there anyway so who cares. If we used it I'd redo the piping to reduce the head losses. For comparison purposes, this is a 1500 sf brick house the Dallas, TX area, 2 adults and 3 small children, two bathrooms, built in 1971, pier and beam construction. In my opinion based on this data it is kinda crazy not to use a tankless.

This saves energy because you must consider that the unit is 82% efficient, vs the electric tank water heater which in the grand scheme of things can NEVER be more than about 31.5% efficient. Electricity is generated at a plant where there are tremendous losses, then there are transmission losses at about 7% (already accounted for in the 31.5%). Check ou the DOE website. It's rediculous to heat anything with electricity unless you run it through a heat pump, you can easily move more energy than you expend with a heat pump.

FYI, to dispell any myths about the $300 tax credit of 06 and 07, I let myself get ripped off by not researching it enough. You can only get $300 per household (I knew that going in) and you CANNOT take the child tax credit if you take the energy tax credit. I'm still coming out way ahead though and I did not look into it any deeper at the time because I didn't want to talk myself out of it. Get one, you won't regret it.

My next water heater will be this one: Vertex

I ran the gauntlet weighing out the two and still prefer a vessel based system. In addition, our residence has a true hot water recirculation system, and the tankless do have a solution that requires a small hot water be installed, but not only does that defeat the purpose it also shortens the warranty period of a tankless. Also, and unless you have the tankless underneath you sink, you still have a lag between the time the water gets to the faucet; obviously shorter runs equate to less wait, but a recirculation system solves this issue. If you lose electrical power, and have no electrical backup, you also lose your tankless' ability to heat. Our recirculation system is well insulated, on a timer, and movement activated, so I am sticking with a vessel.

Fred derf fred:

I too was set on going tankless - till i saw the upcharge. It is coming to about $5,750 more to go with (4) gas tankless (Rinnai 94LS 9.4gpm top of the line) compared to State gas water heaters - as spec'd in the drawings of our house. I did research and found out that gas tankless do have an EF (efficiency rating) of .82, however GAS (i believe you compared electric tank) tank heaters commonly have .62, and a few have .68 efficiency.

This results in savings of tankless is about $250 per year, for all 4 units combined. So it would take me more than 20 years to recoup the cost difference. This was based on a formula as provided by the dept. of energy. Additionally, State, who sells both, has a 'calculator' on their website that corraborated the results.

Also, please note that your existing ELECTRIC tank heater was very OLD. New, gas models are much more efficient so I do not think it is a fair comparison.

I am no expert, but these are my findings.

I would greatly appreciate any other comments ASAP as we are about to make the decision on going tank or tankless

Why would a residence require 4 - 9.4 gpm units?

Is this a hotel?

Combined with cold are you telling me you need or use 45GPM+ for bathing all at once? Check your water supply line, what is its capacity?

Have you or are you prepared to install as a minimum 2 - 500 cu ft gas meters with little room for the other fixtures? Is that going to require a 2" gas line?

Perhaps you have a large single story house with large tubs in every corner that you wish to have a dedicated heater close by for?

The recently signed stimulus handout now provides a 30 percent tax credit (formerly $300) on the purchase and installation of gas tankless heaters with energy factor over .82. The credit is up to $1500. I had been wavering on my plans for tankless as a backup to my solar hot water, but I think this makes it a no-brainer at least in my particular situation.

All installations between Jan 1 2009 and Dec 31 2010 are eligible.

I've also been considering a solar system and looking at potential back up options. In my area, it looks like an electric tank would make the most sense as a backup. It has low capitial costs and when I'm most likely to need it (winter) the energy costs are low. Our electric rates are 4.7 c/kwh in the winter after (800 kwh) and 10 c/kwh all other times. So, the most expensive standard water heater is the cheapest as a backup.

Another situation that may be worth while for some would be to use a tankless in a combi role. Where it provides domestic hot water and heated water for a radiant system. This would also work with inputs from a solar system.

Thanks for the heads-up on mo' money from Uncle Sugar. I wonder if the blind FEDGOD programs for tankless even care about: 1) INcoming water TEMPs; and 2) INcoming water HARDNESS (re impeller Liming)...??? These two CRITICAL parameters are missing from many of the "lively" threads on tankless.

Being at latitude 26N (Ft Laud, FL), I feel almost guilty for not being massively solar-powered... OTOH, it has to be HURRICANE-PROOF, which means serious $$ and Mechanical/Civil Engineering.

It also means you pretty much have to wait for replacement time in the 15-20 year life-cycle of your concrete roof tiles, otherwise the tear-up costs and leak potential would be off the chart.

I would McGuyver up a conv. tanked unit for night-time storage, so that I didn't leave a bunch of hot water on the roof all night, cooling off.

The State.gov occasionally has solar incentive plans, but they're meager and are quickly subscribed/tapped out before I even find out about them. :( You can bet the usual vested interests lobby hard to KEEP those programs meager... GRRRrrr.

fixizin,
You must be difficult to carry a conversation or live with.
Why all the paranoia all the time?

Yes tankless have flow rates and production stats, based on BTU, incoming water temps and efficiency of unit, all published and easy to understand, so what has that got to do with the stimulus plan and it's benefits to us?

No paranoia here, just a review of (*ta-DAH*) PAST PERFORMANCE!

You've NEVER visited anyone in a VA hospital, nor accompanied a parent or other elder to a Social Security office, I take it? Thought so. Just keep watching those Obama sound bites, and burning that clean coal, lol... ;')

Also, in mentioning BTUs, water temps, and efficiencies, you conveniently "forgot" the hardness and impeller liming issue... IIRC, the threshold for that budget-killing phenomenon is 11 GPG solids... that's a big part of CONUS.

I'm sorry, what has Obama, VA's, SS have to do with published performance data of tankless???????

Acceptable water quality is also outlined in the manuals, choose to treat your water if necessary, or forgo a tankless, and replace the tank often.

Why do you act like it is a conspiracy?

Government Paranoia, I'm sure. Please take your meds.

BTW, not all tankless have impellers, and the ones that do, it is not the impeller that limes up on a flash heater. (You are mislead)

GPG-Defined as 1 grain (64.8 mg) of calcium carbonate per U.S. gallon (3.79 litres), or 17.118 ppm

If your water is 188.3 grains hard, you are not a candidate for tankless, please explain why your poor water quality is a government problem and conspiracy?