jay, I will try to give a useful answer. We mounted ours outside so the venting issue was taken care of. The sizes of the units and flow rates are on each manufac. web site. Noritz is the one we bought and it has a very comprehensive site. The electric might be better for you and mount it on the wall in that closet. Much easier for you. Do a Google for electric demand waterheaters. Good Luck...Caroline

Thank you Caroline! If the electric version obviates the need for considering venting that seems like the way to go then. Outside mounting (or changing anything in the walls of the building) unfortunately isn't an option for me.

And thank you pinocchio - I can probably check the vent size or get the super to help me with it.

I'll go google for electric demand waterheaters now...

Best,
Jay

I just installed a Takagi T-K1S tankless water heater to replace an 8-year old, 50 gal tank. Performance has exceeded my expectations! According to the remote controller that I purchased with it, the incoming water temperature is 68 deg. and the 190,000 btu unit has no problem heating the water to 122 deg within about 10 secs . With the remote, I can adjust the temp from 95 deg to 176 deg with the press of a button. I am able to fill a bathtub in one bathroom while the other shower still has perfectly hot water. Count me as another satisfied tankless convert!

Im glad it works for you, mduett, But you said: "With the remote, I can adjust the temp from 95 deg to 176 deg with the press of a button." Huhnh? That is nice and warm: 176°. In fact, that is enough to cook pork to a well-done internal temperature.

This is called, scalding. So if the water goes to an anti-scald shower/tub faucet, it will be reduced, and allow more COLD. But I was under the impression that water heaters were required to be limited to something like 140°F.

Whatever. Ive only installed one of these units and the customer is extremely happy. Furthermore, it is not a Noritz, Rinnai or one of the classic pricey units. It is a Bosch, sold thru Lowes; and it installed very easily.

One interesting fact, is that a demand-type heater has very little water in it, so that it weighs little, even when full. It can hang on the wall of conventional frame construction. The unit does, almost, double the price of a water heater. But it is very efficient.

FWIW, some heaters qualify for a $300 IRS tax credit. Bosch is not one of them.

Pinoke

I think that washing a load of laundry in very hot water would be the only time that I will use this feature. I do have the code-required anti-scald device on my tub/shower.

My electric tankless can't be set higher than 140°F, and that requires a one-time adjustment of a programming option, otherwise the max is 125°F. I use 140°F occasionally for washing whites. My washer takes only about 5 gallons of hot water for a fill. I have the washer's hot tap adjusted for 1.5 GPM flow rate.

millej, DO have your venting checked out (this implies your current unit is GAS-fired), but do NOT assume your closet has the WIRING to support an ELECTRIC demand/tankLESS WH. Indeed, absent any facts, I will give you 20:1 odds that the necessary 220V wiring is NOT there, and that it will cost you a bundle to "make it so".

I note with wry amusement that the "helpful" hankb posted his long PRO-tankless screed the same day he registered here; same with mduett and his short PRO-tankless message. Not surprisingly, neither of their homepages has ANY details, not even the geographic REGION, which all agree is a HUGELY SIGNIFICANT factor in tankless usage.

This same-day-registered pro-tankless spamming is fulfilled in the following tankless thread by vnzppr.
http://ths.gardenweb.com/forums/load/plumbing/msg0300144932745.html?12

There's probably more threads, but you get the picture... ;')

I think we can safely assume these poster(s) are paid SHILLS from the tankless industry. A LEGITIMATE APPLICATION of a technology does not require this web of deceit and evasion to prosper.

fixizin, my tankless experience actually goes back to 1992, when I was stationed in Okinawa, Japan and lived in an apartment that had a Rinnai unit providing endless hot water. I was so impressed by the performance of the unit back then, that I vowed to someday purchase one of my own.

My new Takagi unit is installed in the basement of my house in Bellingham, WA. I chose to install it on the opposite side of the house from where the old 50-gal tank is located. This worked out best, since all of my hot water points of use are located on this side of the house. It is floor-mounted/wall-secured and vented horizontally, directly through an old 2' X 2' window.

LOL, who would've thought there'd be conspiracy theories for plumbing appliances! Yes, I guess the fix IZ in, hehe.

Yep, you KNOW the fix izz in, and it bothers me on 2 fronts:

1) the smoke and mirrors LYING to consumers, most of whom don't have the technical moxie to do a valid comparison on their own. They are filled with false anxiety that while they're off at work and school, their conventional WH is at home, leading a secret life, burning all sorts of energy keeping the water hot... insulation makes this simply NOT true.

2) YOUR tax dollars subsidizing a dubious technology which has NOT shown an energy savings which warrants said subsidies.

Sure Europe has high density living and historic building preservation issues which might justify tankless, but Euros in general don't take as many showers, or wash as much laundry, plus most of America was designed for TANKed WHs, and that's what works best.

PS: Someone email beaglebuddy, and tell him his thread STILL will not die, LOL!

I am so truly curious about all the "expertise" on this board. Has anyone of the rather riled up posters done the research to know what the USGeo Survey winter water temp is in the various areas they so warn us about? Turns out that water underground is not all that cold, folks. So, if you are interested in tankless--a time tested, widely used, efficient and economical alternative which may or may not be appropriate for your home or life style or which may require more mental horsepower for the installer than is available in your area--then do your own research, call various mfg reps and you will learn a tremendous amount that some of the bloviating on this thread obscures.

My real question, though, is why are some of the posters so threatened and personally engaged in a hostile campaign when I cannot believe any one is forcing them to use a technology they so loathe. It seems, well, disproportionate to the "threat", whatever threat that is.

Happy heating to all--however you may chose to accomplisht that feat.

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'll leave all the specs to you stats stars. I'll just point out that I have a wonderful spare space in my garage to put something else I need to store or use and I have no worries of leakage. I LOVE MINE!

Let me preface this by saying I am a right of attillia the hun conservative that hates the tree hugging, prius driving, green on the outside red on the inside wackos as much as the next guy. So my concerns are not energy efficiency or saving the planet or whatever, heck I look for the most inefficient item in most consumer goods.... That said I think I may have a valid point for installation of a tankless unit(s) at my "weekend" house on the river that I may spend 20 days a year at. The two factors I am looking at are; 1. it is a manufactured home for the PC police (trailer to me...) so it basically is a 14ft by 80 ft box of matches as far as I am concerned so I am not real fond of having any gas appliances in it at all and 2. I am worried about a breach in the tank of a traditional heater since the floor is a single 3/4" layer of sawdust held together with glue that would fall apart and destroy the entire house if a tank breach occurred and water stayed on the floor in my long absences. I am about to replace the old poly-buytle plumbing and the complex set up of T's and eL's in the water heater closet with modern PEX and a manifold set up that I can cut the water to a specific point or the whole house from inside the house as well as sustain any accidental freeze up (PEX wall is flexible enough to sustain a freeze). I also am going to replace the 1982 vintage 45 gal Nat Gas tank. Tankless would be nice since closet space is at a premium and any recovered space is needed. I have one bath with a tub/shower combo, sink, and clothes washer and the kitchen sink and dishwasher. I think the negatives others are seeing would be aliviated by the minimal number of taps and, correct me if I am wrong, the fact that the heater and manifold would be on the same wall as the tub/shower tap and pipe runs would be approx 12 in. to tub, 4 ft to sink, 7 ft to washer and 15 ft. to kitchen should = fast temprature recovery on start up. My questions are what would be the correct size unit to buy, and should I use one unit for the whole house or one unit for the bath (tub/shower, sink, clothes washer) and one undersink unit for the kitchen sink/dishwasher?
Thanks for your input...

How about some real world gas experience?

We have now lived with a gas Takagi T-K2 for 13 months. Two adults, with the master suite about 80 feet as the crow flies from the unit -- pipe length easily adds 20 ft. We have the optional wired remote temp unit. We just upped the output temp from 117F to 122F (for dealing with cooler groundwater now.

We get hot water in our master shower in under 20 seconds. The sink faucets take about a minute at 1/2 open -- which they would with a tank too!

Our gas consumption, in MCF, was: June 1.4/July 1.1/August 1.2/Sept 0.9/Oct 1.2. This *includes* gas used for gas dryer and gas range and no furnace heat so far. The monthly cost for that here ranged from $20.62 - 23.49, most of which are transport and service fees -- not gas charge.

It includes 4 loads of wash per week (warm water wash only), 2 showers and 1 bath per day, 2 dishwashers per week and daily kitchen, bathroom tap use. We have no issues with guest showering at the other end of the house, upstairs, when we do.

We love the damn thing and do not miss throwing away money to heat 50 gallons of water 24x7x365.

And to correct one mistatement waaaaaaaaay upthread. Unlike a gas tank heater, you will have *no* hot water when the electricity goes out. Electricity controls the internal sensors and thermostat and valves. My wife discovered that last week about 8:15am, after I had left for work, and a storm blew through and darkened the neighborhood for 2 hours... ;-)

And, me being the "next guy" here, I also want to add that I don't hate "tree hugging, prius driving, green on the outside red on the inside wackos" and therefore wish you good luck with your quest for knowledge.... ;-)

Just for the heck of it, I see that there are people who "hate": "tree hugging, Prius driving, green on the outside red on the inside whackos."

FWIW, I consider that to be too far to the left. However, I have recently been reminded not discuss politics on this forum. So, I wont.

Nonetheless, plumbing-wise, I find it interesting that the value of conservation-ism depends so much on whose money is being discussed. Hate to have to mention this; but, on the list of people who have no HOT water, first should be the poor.

I wouldnt be allowed to say this if it were a political thing.

Fortunately, it is not. It is a mathematical thing. Have a happy computation.

Pinoke

That was less of a political statement and more of a , don't give a rat's butt about conservation, have these two specific reasons why tankless may be good for my specific set of circumstances, so shut up with the arguments about how tankless only saves $1.00 a year over tank units blah, blah, and answer if anyone confers that may specific set of conditions sounds like a good fit for tankless and profer up facts on how to figure the calculations on sizing the unit (I'm an attorney not a physicist....) My opening statement may have been a bit tounge in cheek (it's a literary devise called sarcasim) so lighten up. After all I wouldn't be offended if you made a comment regarding my being part of a vast right wing conspiracy out to destroy the planet or my "irrational fear of government and all the good it does", heck I'd have a laugh with you on it... Just a little context... GT

Ah, the great melting pot! I love an attorney who knows what species he is most associated with, IllinoisRiverRat; even though, I tend not to care a great lot for attorneys, as a rule.

Since no one in their right mind would re-read this thread, from the simple one-liner it began with, to this point, Ill just say, that there are different strokes for different folks. So that means, tankless and storage systems each have a place in a diverse economy, and a diverse population with a wide variety of locations and climates.

My guess and it aint a bad one, right or wrong is that, as a lawyer, you might be phishing for a great lawsuit. Rather than to just enjoy the warm-diaper feeling that comes with a great new innovation, you could be searching for a product liability. But, I only say that because you have confessed your guilt here; and the 5th Amendment requires I play it both ways.

Actually, IRR, I think you make a good point. It depends on the user. And dont be mistaken: I actually do give a Rats A, as you can see! On conservation? I look at it this way. This is the greatest land in the world and has all the natural resources we need to live peacefully together for centuries, while we educate our kids on how to power a spaceship from a urine specimen.

Meanwhile, anybody that tries to take this away from us: we should decapitate them and consider an apology, in case they still are alive.

Makes our mainstream look pretty leftish, dont you think? OK. Enough of that. Winters coming. Its time to get the HOT TUB on the deck and heat that puppy up to 106°. We can heat it with the drippings from chicken fat. Free-range chicken is OK, but the force-fed ones are better. (Taste just like chicken!)

Pinoke

I don't know much about the flow rate and all that technical stuff.

All I know is that the regular hot water heater didn't hold enough to fill the jacuzzi tub with hot water. It was quick to recover so we would fill the tub in 2 sessions, waiting 15 minutes between each session.

With the tankless hot water I can fill the tub in one sitting, adding cold water in to cool it off.

We are 2 old folk, so running 2 things at once isn't real necessary. In fact, don't know if I can or not, though husband said not when he installed the tankless.

My only negative is that the model we got has no temperature setting, (I know, it has something to do with water flow speed) so the hot water gets REALLY hot if run straight hot. We have no kids at home so for the 2 of us, it isn't a problem.

What do you call 1,000 lawyers at the bottom of the ocean? A good start. See I can laugh at my profession to. By the way all I do is real estate title work, not litigation let the trial lawyers have all that stress they want, I really don't want to drop over dead at 45 of a heart attack.... So I guess I would have to hire one of my friends to file the above speculated product liabilty suit just like anyone else!! Not a bad idea though, thanks for the suggestion! LOL GT

I once was into politics. (Today, politics is into me. So, were even.)

At that time I went to a political convention. (I wonder, is it OK to say that? Yeah, I think it is.) It was the one (1984) when Ronald Reagan was nominated for a second term. And so, you might expect lawyers to be as welcome as bedbugs at the hotel.

But, out in the hall there were a group of fertile women, all lawyers wives, I guess, who were wearing sweatshirts that paraphrased the classic quotation from "King Lear:" "OK. First thing we do: KISS all the lawyers." I loved it just poetry at its finest.

BTW, when I grew up, "real estate" was a household word. Yknow? You just used it. No one ever asked what it meant. So what does it mean? Is there estate that isnt real? Maybe I dont know what real means. But FWIW, it does suggest that someone has been lying about whats what for a few centuries anyway.

Its like, if you have a business, a horse-shoe-ing shop, for example. Who knows what that is worth? Better you should own a tire store. That way, when you have a flat, it doesnt smell like oats. (It will, however, smell like a Harbor Freight Outlet. You cant win.)

Anyhow, I dont like words or phrases that have state in them. "Real estate" is fraught with danger. So is, inter-state, intestate, lying in state, "the people of the state ," "Please, state your name," "This a "State"ment; NOT a BILL. (Wait til you see the bill!)"

Its a rhetorical question, IRR. I know you know that. I just dont want some moron hijacking this thread and taking off on a tangent. Incidentally, have you ever gone-off on a tangent? Powerful stuff, man. I had an uncle who ate 2 for breakfast everyday and he died of ass-fixation or so it said on the death certificate.

Hate to say, but it was a sorry state of affairs. Another nice thing about demand-type water heaters: they dont take up a lot of space or, as some would say, real estate.

Doesnt anything make sense anymore?

Well, yes. But sometimes it takes a Philadelphia Plumber to explain it.

Pinoke

By the way all I want out of life is an answer to the two simplistic questions of my first post, which no one seems to addres. How to mathimatically figure what size tankless unit I need and if anyone else though it was a good fit for my set of circumstances. Once that is answered, if I am struck dead I will have died a happy man. Also philadelphia plumber, isn't state a manufacturer of tank type water heaters; do I smell a conspiracy here?

Just as the descripitve of a group of cows is called a herd and a group of geese is called a gaggle do you know what a group of lawyers is called?

That's right it's a conspiracy of lawyers, look it up....

Quit trying to get back On-Topic. Youll confuse the people who start at the top. If you really need to know the answer, its best to post the specific question in a new thread. Then, the most relevant answers will appear. In fact, you can actually get the answer from a master plumber, who will calculate your pipe sizes and everything. Great place, this Plumbing Forum.

However, for the purposes of answering your simplistic question: "How to mathematically figure what size tankless unit I need and if anyone else thought it was a good fit for my set of circumstances," I should point out that that is really only one question followed by its own answer.

You see, one doesnt calculate to get there. You go to where they sell them and you buy one on Faith. Im serious. A demand-type water heater doesnt come in sizes like one of them State® water heaters. It is sold in limits. So, for about $500 depending where you shop you can get one in gas or electric that will sure as heck work for approximately one major fixture at a time.

So taking a shower or washing dishes or washing clothes are all things that one smaller unit can do continuously. If you have a greater need, such as two showers running at the same time, while someone is washing a car and shaving, you might want to consider the pricier ones, more than a $1000 for the unit.

When you add features, such as heavy gauge metals, stainless steel and nice plastic nameplates, the price can be several thousands of dollars. But you end up basically with what everyone likes to have from a water heater: HOT water.

Now, depending on an individuals personal finances, no matter which unit one buys, it will always be over-priced; and it will take a long time to get to the payback point. Of course, if you use more HOT water because it feels so good, you get there faster. For that reason the Federal Government is offering IRS credit to people who buy certain demand water heaters.

You didnt think they would let just anybody get a rebate, did you? No, for the most part, the $500-units dont qualify. The whole idea is to get millions of people to have these luxury units in their homes and then they can tax the living s--- out them. So dont spend your tax credit, yet. Im thinking of getting on Social Security and Im going to need the money.

Say, did you hear about the lawyer that ran for judge, got elected and rose up to the high court and then was convicted of a crime and sent to prison for life?

I didnt think so. Me neither.

Pinoke

"Say, did you hear about the lawyer that ran for judge, got elected and rose up to the high court and then was convicted of a crime and sent to prison for life?"

Hadn't heard of that one either, but have heard of a court system that figured out how to become a profit center by bringing inditements on "financial crimes", i.e. the things that used to be a matter for the civil courts, and will freely Nolle Prosequi those same said charges after restitution (basically what would have been the judgement amount in the civil courts) AND several thousand dollars in "prosecutorial charges" are paid. Sounds kinda like extortion to me, but hey they are the good guys, right?

This is the most bizarre thread I have ever read. I think Mr. Pinnochio has got a sliver (or some shape of wood) caught up his, er... somewhere.

Sorry for the mean statement.

I guess it would be a good thing if this site would let us edit or delete our posts.

It's still a bizarre thread.

Youre still new here, web-lyncher. So stay tuned for some really great writing. I have to say, there has already been some great stuff but unfortunately, most of it has been deleted by the webmaster.

Thanks for the compliment. Sometimes I wonder if anybody notices. After all, who is going to read a thread that goes on and on about tankless water heaters? Oh sure, there are such people, but they are boring, and their eyes are too close together.

Not that they arent welcome here anymore that anyone, including me. But there just isnt that much to say under one topic. But for the real studious types, who want to glean everything they can from a thread about water heaters, I cant help thinking even they have a funny bone in them somewhere.

After you get past a hundred messages, its time to think about things bizarre. For instance, I have always wondered how women hook them things with both hands behind their backs.

Uplifting; dont you agree?

Pinoke

Interesting thread, however, the entire problem was identified, but not addressed, at the begining. Some people simply don't want to ever have to think about the heating, cooling, sewer systems in their homes. That's fine, although it may lead to health and ecological problems, if you believe such things exist. I remember using an outhouse, a septic system, then city sewers. Not having to deal with that crap (pun intended) was a godsend. But sometimes, you just have to deal with it even if it's not simple.

The desire to Keep It Simple (for the) Stupid slows the adoption of most new technologies. It's similar to those who said the automobile would't catch on because you couldn't stop it by saying "whoa." Cars couldn't swim rivers. You had to stay near gas stations. Cars were a joke because they failed KISS.

You only need to read the posts that contain words like "BTU," "ground water temperature," or "gpm" and you can see that tankless water heaters can't meet the KISS standard. With tank heaters, the question is 40, 80, or 120 gallons. Period.

My neighbor put in hot water tank and a circulating pump in his new construction. I'd never seen anything like it. It has an expensive little pump that constantly circulates water from the tank, cooling it off in copper pipes, and causing the tank to have to cycle on even more. All this so that he gets hot water in one second at the third floor bath. Whoopee. It probably more than doubles his standby costs of storing hot water.

I used 3/8" PEX (1/2 the volume of 1/2 copper and 1/3 the heat loss) for my plumbing. Takes me 7 seconds to get full hot water at the fixture that's furthest from the heater. Only 1/2 a whoopee? Maybe. My whoopee comes at the end of the month. We both travel a lot and are only home about 1/2 of the time. My electric bill is always 1/5th of his. I'm sure a large part of that is my tankless system. I can only think, based on his wasteful hot water circulating system, that the rest of his energy use is similarly silly.

What is needed in a discussion of tankless heaters is a list of the items to consider for those willing to examine the complexities that confound the stupid (the "non-KISS" crowd). One of the posts above claimed that tankless heater manufacturers were "LYING to consumers, most of whom don't have the technical moxie to do a valid comparison on their own." I think that the facts and numbers are out there, and it isn't rocket science. Technical moxie is what the non-KISS crowd thrives on.

It appears that the one unknown item may be the heat transfer efficiency, i.e, how long does it take for the unit to reach it's rated output and how much fuel is sacrificed in order to produce instant hot water. Since most of the dissatisfied users have the gas or propane units, I'm guessing that's where the problem lies.

The electric units that I'm familiar with have the elements immersed directly in the water, as does an electric tank heater. At low flow, the first element comes on. The other two come on as flow increases, decreases, or the incoming water temp changes. Essentially all of the electric power is converted almost instantaneously to heating the water. There is no "excess heat" going up a flue. The energy loss resulting from storing hot water is saved, thereby making the electric tankless much more efficient than a tank.

Each electric element in mine has its own 40A fuse, so it's not something that can be easily retrofitted to replace an old tank. In fact, replacing an old tank with a tankless heater doesn't always work. The tankless heater has to fit the plumbing system. In some cases, the home owner may have to change habits or life style to fit the heater. This can drive the KISS crowd crazy.

I don't know the relative efficiency of the gas heat exchangers. Does the tankless gas sacrifice some efficiency in order to heat instantly? Seems to me that there would be some inefficiency from trying to instantly go from hot gas to hot water. The gas hot water storage tank may be able to save some energy because it doesn't have to heat instantly. Don't know. Something for the non-KISS people to investigate. Use some of that technical moxie.

For those who claim that the demand units can't produce enough hot water for them, the answer is simple enough for even the KISS crowd. "USE LESS WATER." A good friend of mine's wife was demanding that he remove their tankless unit because it made the temps fluctuate in the shower. I talked him into putting an in-line shut-off valve right before the unit. Turn the shower on, turn the valve down until the either the heating starts to cycle or the shower flows less water, turn the valve up a little more, and no more problems. Technically, the shower probably flows a half gallon less per minute, but the wife couldn't notice. No joke.

Mark

you are in for a big surpirse some day fellas......

once the TANKLESS starts to lime up and break down and need maintaince you are going to be crying like a baby.....

all those big saveings you think in your mind you are saveing with a tankless will go to the service man at $150
per trip twice a year when the flow rate declines and
you have to de-lime your tankless heater twice a year...

FELLAS---you are going to have to pamper your tankless heater like a little baby.
Eventually your wife will threaten you with divorce if she has to put up with it another day... then you will have to switch back to the good old tank type to keep your domestic life from going
down the toilet.....

just wait and see....

go to my web site and click on tankless for more info

weilhammerplumbing.com

Master_Plumber_Mark, unfortunately I don't have a wife to alert me when performance deteriorates. In your experience, how long might it take for that to happen if my water is ~11 grains hardness? I didn't choose a tankless water heater, it was already in the house I bought. I've found that I like it, but whether I'll get another tankless when it dies or switch to conventional tank, I can't say until all the variables are in.

"Lime up"? What's that? Again, do the research before deciding. I've never heard of lime up, so I haven't had that problem with my tankless or my tank. My guess is that, if your potable water is sludge or contains high soluable concentrations, you will likely have problems, and not just with your hot water tank (or tankless).

From what I have seen, the tank system suffers from funky sediment because it heat cycles large quantities of water in a tank. Things settle out in there and cover the bottom heating element. I've drained sludge out of a tank before when replacing an element. Never seen anything similar in a tankless system.

My demand heater holds a little less than one liter (approximately four aluminum cans of Budweiser in American Standard Measures), so there's no accumulation of sediment, lime, or Legionaire's Disease. Do a Google search on "Legionaire's Disease" and "hot water tanks" for a fun read.

Mark

Hi all,
17 yeas ago I had the misfortune to install a Thermar brand tankless gas water heater in my home. Now THAT was a POS! At least twice a year the rubber diaphram needed replacement. Only 1 parts house in the USA had Thermar parts and the price grew more exorbitant each year.
Not to mention having to crawl into the attic to take the darn thing apart and put back together with no drips.
Suffered through several years of parts availability, higher gas bills, bad thermocouples, not enough flow, thermostat shutting down burner at random times, and so on.

Never again!
I'm quite happy with my gas tank type heater, thank you.

Manufacturing methods for both tank and tankless heaters have come a long way in the last 17 years. I imagine that a performance review of your computer of 17 years ago would also be considered a POS by todays standards. Time and technology marches on.

We have a tankless (Takagi, I think) with a hot water recirculating system. We put it in to replace two gas hot water tanks. Luckily, I was home the day one of the hot water tanks decided to give up the ghost, so we were spared the expense of major water damage (and given that I'm in the midst of repairs to another house which suffered $40,000 worth of damages from a leaking toilet, I know how bad water damage can get). We couldn't be happier with our system...instant hot water at the tap, and endless to boot. We can run all kinds of things without a drop in flow. We have peace of mind knowing there won't be any more possible hot water tank disasters. And we gained a closet!

I don't know what our possible gas savings are yet (don't have previous years' info to compare as we haven't lived here that long) but I do know the tanks were making our bills pretty high... When we turned the temp on the tanks down during the summer, our gas bill dropped dramatically.

In short, we like ours! :)

hey, whos keepin an eye out for binladen? lol. anyway........... I think a tankless HW is a good application for an occasional use powder room or a guest bath.

put in a rinnai tankless love it. also i am trying to save our earth for future generations one step at a time

Tankless units are common in my area for customers calling me with no one to service them. Their heat exchanger compartments are super thin compared to the thickness of a tank heater.

When they break, you spend dearly. I'm glad there are ginny pigs to start this product's beginning.

What owners/sellers don't realize that these are gas units that require electric to operate. No saving the earth when you have coal burning powerplants turning the generators to run your gas tankless unit.

And the electric ones? The meter spins a mile a minute.

Parts are extremely expensive for these units along with availability of trained hands to service them.

GOOD LUCK

Maudeb7 - I understand there are several reasons to favor a tankless, but I do not understand your comment about "trying to save the earth for future generations". I posted on another thread on this forum about hearing the president of Rinnai America on a radio interview (BTW, he was quite impressive in his knowledge and expertise). The surprising thing was that he said you should not buy a tankless heater if your goal is to save money or to save gas. Particularly in a cold climate, the gas usage for a tankless can be really high. Again, this is the guy from Rinnai talking. He said you should buy a tankless because you want endless hot water. Also, it has the advantage of a much smaller footprint than a traditional tank. But a tankless will not help in "saving the earth". Also, I hate to think of all the tank heaters going into landfills, as their owners discard them in favor of a new tankless.

Saw a friend's Bosch Aquastar opened up yesterday. It's an older model, no electricity or electronics involved. They've had it at least 5 years. He was dealing with a clogged (actually disintegrated) filter in the input water line. The heat exchanger (looked to be at least 10" in height) is similar to a radiator -- water line zig-zags through it from bottom up. He turned on a faucet while the cover was off, I saw the burner ignite. With the one faucet running, the flame was somewhat low. Less than I expected based on what I've heard about gas consumption. He turned on another faucet, flame height doubled. I don't know how intense it can get, what's the maximum output. Seeing the operation, it's understandable that there's a delay until hot water arrives at the usage point. The heat exchanger has to get hot, and the standing water in the line purged. Requires 1/2 GPM flow-rate to activate. Successive usage would be less delay after the exchanger gets heated ... of course unless/until it cools substantially. Doesn't appear to be a way to set a specific operating temperature on this older unit. The vent stack also isn't as "hefty" as I expected based on what I'd heard .. but maybe this is a moderate capacity unit. Again, based on what I observed yesterday, what I've heard my friends say in the past, and my personal experience with electric, electric tankless seems more able to modulate for maintaining the target temperature and dealing with flow-rate variations. I imagine newer gas units with electronic control systems are also better.

WOW, as somewhat of a newbie and as a simple homeowner who is simply trying to survive her remodeling project w/o making too many more mistakes, you guys seem like a lot of people with your own agendas. We have a master bath with two showers, a tub and 2 sinks and a laundry room nearby. We also have a basement with 3 other bedrooms and baths and laundry room that are used only when our 5 children and 11 grandchildren come and a kitchen, of course. I was really considering putting in a tankless near the master bath and laundry and then just using a tank system for the kitchen and guest rooms. This project has had lots of surprises and my husband and I are retired and tired and don't need water problems. After reading all of this I can't figure out if there are those that are simply hell bend against change b/c they don't, perhaps, have the expertise to do the installs or have some other personal agenda or whether the tankless WHs are truly the devil in metal and we will be forever doomed if we own one. I don't much care about saving 15cents a month or whatever. I should be lucky enough to live long enough to receive that payback. I do care, however, that we have plenty of hot water when everyone visits so I am not scheduling everyone for showers the next morning at dinner the night before. Can someone please just give me an honest answer about whether tankless would likely work for us. We are in Michigan but I don't really get the cold weather argument b/c as far as I understand, everything is about the same temp everywhere once you are 4 feet or so underground--isn't that the whole principle behind heat pumps? Oh well, what do I know, I am just a blond, a women and a patent attorney.....guess you know why I need some help.

wldsyd,

No personal agendas and NO I didn't read this entire thread. Don't need to.

Just do this and let us know how it works out. Buy the most expensive tankless that has at least 12 gpm rating so that your not "minimizing" counting the numbers of showers and people to gather an equation on what you need.

A 12 gpm unit should cover all basis. THEN, pay whoever you want, preferably not a plumber since you don't think were able to handle the new technology and be able to install it.

Get a handyman and let him "learn as he goes" and hopefully you'll get the hot water demand you are looking for.

Water heaters are around $1000 installed, tankless you can figure double or triple that figure. But you want hot water and don't want to save 15 cents.

Go for it and make a example for the rest of your neighborhood that you can take endless hot showers. Just don't tell them how much you paid to do it.

LOL! No personal agenda? Maybe not, but sure is a buncha vitriol up there.

I have installed a few takagi tankless water heaters (upon request) and dozens of rinnias. I don't know about any other brands of tankless products, but have heard bad stories about other brands. I am also certified to install only the rinnia.
I don't know If it is ok to talk pricing on the site, but i charge $1600, $1800, and $2000 for three different rennia units in new construction. The $1800 unit I install 80% of the time. I started installing them about three years ago and am installing more every year. My customers love them and I have had Zero compplaints on them so far. The reps have told me they are a 25-year product (the same as high efiency biolers). Most water heaters I change out have lasted 10-15 years. The rinna's burn at 84% where a regular water heater burns 74-76%. The tankless also is never working when you're not using hot water. Last year my customers also cashed in on a $300 tax rebate for their tankless. We have figured they pay for themselves in 4 years. If any of my customers have a problem that I cannot fix, they will have a new unit hanging on their wall within the hour. I have access to the supplies and support in my area. I have one tankless water heater and two biolers I install because I can service, trust, and own those products.
Dual flushing tiolets, Ground source heat pumps, Solar pannels, Tankless water heaters are all wonderful products that have been proven in other countries. It takes good installers with service contracts, informed home owners and Government leadership on a national and local level to make it work. Green builing has got to be our future. We will look back in 30 years and be able to see the impact they have made. Our building and enviroment are a symbiotic relationship and our pocketbook cannot forever come first.

If you are all so angry that you can't even stomach and tolerate questions from homeowners who truly do not understand the technology and are simply trying to make good, long term choices, then why hang out on these forums? Can't you imagine that after 11 months of living in the middle of a major remodel I don't need anybody attacking me. Thanks for the sarcasm.

Plumerrick....thank you for the kind response. Do I understand you to say that you would suggest Rinnai over Takagi? We could install this unit right over the shower and vent directly to the outside. We could also easily install the gas. For 2 shower heads (and a rain shower), two sinks, a tub and a laundry room, what size Rinnai would we need (Of course it wouldn't all be used at once, I would guess that the showers could be going at once or one sink and one shower and maybe a load of laundry but not the tub). Thanks.

I don't much care about saving 15cents a month or whatever. I should be lucky enough to live long enough to receive that payback. I do care, however, that we have plenty of hot water when everyone visits so I am not scheduling everyone for showers the next morning at dinner the night before. Can someone please just give me an honest answer about whether tankless would likely work for us.

Uh, Wldsyd, I'll repeat what I wrote 4 messages above yours. That is that the President of Rinnai America himself said you should not buy a tankless heater if your goal is to save money or to save gas. Particularly in a cold climate, the gas usage for a tankless can be really high. He said you should buy a tankless because you want endless hot water. Also, it has the advantage of a much smaller footprint than a traditional tank.

That should answer your question.

If you are all so angry that you can't even stomach and tolerate questions from homeowners who truly do not understand the technology and are simply trying to make good, long term choices, then why hang out on these forums? Can't you imagine that after 11 months of living in the middle of a major remodel I don't need anybody attacking me. Thanks for the sarcasm.

In defense of Peteyboy's response to you, what I saw in your message was a challenge that said that despite all the previous 140+ posters, you still weren't provided enough information, despite posters' links, despite professional plumbers and installers opinions, despite lengthy explanations of why people felt pro or con, despite explanations of the necessary venting and gas line changes involved in tankless, despite opinions from the tankless owners who'd been living with them. You dismissed it all by saying people had "personal agendas", that the several professional responses were "those that are simply hell bend against change b/c they don't, perhaps, have the expertise to do the installs". With 140+ responses, none of which you found helpful, I cannot blame Peteyboy for his message.

BTW, you can also do a search on this Forum for "tankless", and you will come up with many more threads if you seeking more information than what was provided in this one.

Wlydsd said, "what do I know, I am just a blond, a women and a patent attorney.....guess you know why I need some help."

As a blond woman who does not find the concepts of tankless beyond my intellectual grasp, I am offended by your statement. You mean you went to law school, passed the bar, but still use the "blond woman" card? Shame on you for promulgating the stereotype. It's 2007.

Plumerrick....thank you for the kind response. Do I understand you to say that you would suggest Rinnai over Takagi? We could install this unit right over the shower and vent directly to the outside. We could also easily install the gas. For 2 shower heads (and a rain shower), two sinks, a tub and a laundry room, what size Rinnai would we need (Of course it wouldn't all be used at once, I would guess that the showers could be going at once or one sink and one shower and maybe a load of laundry but not the tub). Thanks.

For all you "Tank Heads" - Is it any different for your tanked water heaters to heat the incoming "supply water" than it is for a tankless model? They are both doing the same job, right? What difference does it make "where you live" and whether you live in a "cold climate" or not? If the incoming "cold" supply of water is 40 degrees it's 40 degree water whether a "tanked" model is heating that water or a tankless model is doing the job. In both case the supply water needs to be heated up to the desired "hot water" temperature irregardless of whether a "tanked" model is doing the heating or a tankless model is doing the heating! Why would that make the tankless model any more expensive to run that a "tanked model"? They are both essentially heating that exact same temperature supply water up to (get this) the EXACT SAME DESIRED TEMPERATURE OF WATER hence, it would cost the exact same amount due to both of the models doing the EXACT SAME JOB! The only exception is that the "tanked" model runs ALL DAY LONG - 24 hours a day - while the tankless model only runs when the hot water is called for! Needless to say, that means (without ALL OF THE STUPID MATH) that it is cheaper to run (not install but run) a tankless model than it is to run a "tanked" model to do the same job of heating water! Now the real comparison is between the amount of WATER THAT A TANKLESS MODEL "WASTES" versus the amount of GAS (OR ELECTRICITY) THAT A "TANKED" MODEL WASTES! Okay, now that we've all finally figured out what we really should be comparing (the running of the two different models), lets debate!