Tankless Water Heaters

This is a very interesting column on tankless water heaters.

I am a "proud" new owner of a whole house Rinnai unit. Because this was a retrofit, replacing a complicated gas hot water/heating system we had issues with power and space for venting where the old system was installed. These restrictions are what made us consider the tankless, as we could install it in the attic and have no problem with space for venting, accessible power, etc.

Here's the problem we've encountered. It's winter and the temparature of the water entering the house is around 48 degrees. The huge rise the Rinnai has to make to produce hot water makes the flow rate unbearable for a family of four.

We are considering a traditional electric water heater to temper the water to say 80 degrees in order to attain the higher flow rates we need to supply our home.

Has anyone ever done this?

Robert,
TaDa! You are one of many who read my column a little too late. Imagine what is going to happen in January or February when the incoming water temperature drops down to 38F! You can install a regular heater before this one. But I would never do electric, I would install a gas heater with an burner that was 50,000 Btus or higher.

Thanks for the reply. We are on coastal Washington State and won't get much colder than this. The main reason I'm concerned about a gas heater is the inadequate space for running ventalation and exhaust pipes. Are you suggesting the gas just for the energy efficiency? Or if I installed the water heater in the attic I could use gas, but I've been a little nervous about putting it up there (although it sounds like people do that).

Robert,
I say gas because the recovery rate of electric heaters is so low. Once you burn through the 80 gallons, you are where you are now!

The comments above refer mostly to retrofits and comparisons. What about builder costs? If I were building a house, what would be my best option for comfort, tempered with energy savings, water conservation and cost reduction? Any imput would be appreciated. Thank you.

I forgot to mention that I'm in the Seattle-Tacoma area of WA state.

Ali,
All of the same conditions apply to new construction. Seriously...... Here is my bottom line on tankless water heaters:
If you want unlimited hot water and the incoming water temperature is above 50F AND you are not concerned about the length of time for your Return on Investment, then get one. You have to sharpen your pencil to do a set of calculations to see when you finally break even.

true if there is no limit on use of hot water (no negative feedback) there is a possibility of using more energy; however, practically speaking there is usually already more than adequate supply of hot water available, in other words most people are not threatened by the possibility of running out of shower water. Americans are used to having plentiful amounts of water in most cases. So in 90% of the cases people might only run out of hot water in 30 minutes, so giving them infinity is not going to make them stay in the shower another 10 minutes.

Bill,

Did you not read the letters above on top of the comments? I have received *hundreds* like that over time. If I printed all of them, this page would take ten minutes to load into a browser.

The point is that *some* people will use more hot water knowing there is an endless supply. Remember, I am not against tankless heaters; I just feel people should know they cost more and there is NO guarantee you WILL save money. Don't believe me? Read the above letters.

Have a question. House is located in southcentral PA. Do to an addition to the original house, we have one 40 gal propane water heater and one 40 gal electric water heater.

Does it make economical sense to replace the two water heaters with a tankless model of appropriate size?

There are three baths in the house, but only rarely does more than one shower get used at once. About two times per year, when kids visit, there might be two showers being used at once. It is more likely that a shower and the dish washer or a shower and washing machine might be running at the same time. MOst of the time, it is just me and my wife in the house.

Lastly, the area where the house is located is prone to losing power. we have a generator that is large enough to run the current propane water heater, but not the elecrtic one, do to all of the other items that are on the generator. I am thinking that a tankless heater could be on the generator and thus provide hot water to all of the baths.

So, my question is, would you recommend a tankless water heater for my situation, if it replaces both current water heaters? and what can you estimate the cost savings per year?

Regards,
Lew Sauders

Lew,
Your comment leaves me perplexed. I wonder if you read everything in the above *page*. Your answers and much more are there. Pay attention to the recent comment about incoming water temperature and what I say about Delta T.

Tim,

Why so much sarcasm? I read all of the "above" information. I could not find anyone who currently has two water heaters to supply their homes with hot water. Thought my situation was a little different.

Here is a thought for you, "you catch more flies with honey rather than vinegar".

Lew,
No sarcasim was intended. I do not treat my guests that way. Sorry if you were offended. It doesn't make any difference how many heaters you have. You have to determine *what* you want. If money is not an object, then buy a tankless heater....... Once again, I implore you to read my column,. all letters, all comments, etc. The takeaway should be: Tankless heaters will supply endless hot or lukewarm water.....at a cost..... that you may not recapture....

Question: I found a bosch power star ae125 for $400 on the clerance rack at lowes's, it retails for $600+. With +/-$100 supplies, I can do the installation myself electrical+plumbing. So, for arround 500$ installed, comparable to a new high efficiency tank. The flow rate is acceptable for my needs and occupants are efficiency minded. After reading all, i'm not sure I should install or return. The idea makes sense, but after reading horror stories about 40% higher gas bills i'm not so sure. The Question is are the energy savings for real or bs?

Daniel,
I have said it multiple times: if you want an endless supply of hot water and you do not care about money or how long it might take to break even, then move forward. But realize that you may NEVER save money. Those emails I got are not made up by me.

I posted a question yesterday about wheather or not the savings are real on these things. More importantly I have a leaky 19 year old rheem 50 gallon natural gaser that eats up gas and was repaired twice last year, I need a new tank or tankless heater regardless. But in my case the total costs are simular. In your opinion are the savings real or bs?

Dan,
The stated energy efficiencies on the products are accurate. Please read all of the column, letters, comments again. You need to do the math to see how many *years* it will be before you break even.

I've written before. I work for a small builder in WA state and our company is having an internal debate with one person stating that 80% of info on the market regarding tankless water heaters is good and therefore our hesitence to install a tankless water heater is unfounded. How can we obtain accurate customer satisfaction and data that is not biased to either side that would assist us in determining if we can afford to make this supposed "green" change in our construction? Can you assist me with this?

Ali,
That is an excellent question. I don't have a dog in this fight. It is my belief that the information you see here at AsktheBuilder.com is accurate. How can I say that? Numbers and physics do not lie. You need to run the numbers. Have you done that with some random gas bills?

If your company is REALLY serious, the task is simple. Do a test in a recent client's house that has an average family - husband and wife and maybe two or three kids. Connect a separate gas meter to a new high-efficiency STORAGE water heater. Calculate the exact cost of the gas used for a one-month period. Then take out the storage heater and install whatever tankless heater you feel is the best. At the end of the second month, compare the gas cost. I am wiling to bet the amount of gas used by each heater will be within 10-15% of each other - maybe even closer. With this data, do a Return-on-Investment calculation. You are going to be blown away at the amount of time (years and years) it takes to break even....... Remember, there is NO COST SAVINGS until such time as you recapture the capital AND interest it takes to pay back the EXTRA money spent to save money.

Tim,

OK, I've reviewed much of your gorgeous writings re: Tankless Water Heaters.

But RIDDLE Me THIS One BATMAN .... I didn't see any mention of my situation in; not only your commentary, but also the comments of your readership.

Here's my situation:

New Construction.
Second Home(cottage)in Michigan.
Only available for use 4/1 to 11/1.
Will be occupied on-and-off from April 1 to Nov 1.
Will NOT be occupied from Nov 1 to April 1.

A tankless seems to make sense for my situation because:
A. When closing the cottage for the winter, I would have to drain a traditional storage water heater prior to every winter. Would such drainage/maintenance be required of a tankless?

B. Since we're in the cottage sporadically, i.e. often there for one week, gone for two, back for 5 days, gone for one week, etc. It doesn't seem like it makes sense to have a storage-type water heater sitting there keeping that water hot, while we're gone for several days or weeks at a time.

Would a tankless be better in my situation due to A & B above? I'm less concerned about the overall cost savings, and more concerned with just the concept. It just seems stupid to have a big 80-gallon tank keeping all that water hot (or even just warm for that matter) while we're away. Not to mention the ongoing corrosion as the water and sediment just sit in the tank.

On the other hand, I am concerned about getting a tankless up in a remote small town in Northern Michigan because I don't think the plumbers have a lot of experience installing tankless water heaters in that locale; and if it breaks, I'm thinking I'll be S.O.L. for many days awaiting a qualified technician and or parts.

OK ... there you go, BLAM, SLAM, POW!!your turn, BATMAN ... ROBIN anxiously awaits your answer!

Scully

entire countries have adopted tankless water heaters to solve energy issues -- it is very improbable that these use MORE energy. 1000 posts can say their unit uses more energy or doesn't work or whatever. doesn't matter. what percentage of these people are legitimate? have they been validated as buyers? no. so let's not jump to conclusions. present only the hard facts -- WHY does your unit take longer than an old water heater? WHY do you use more hot water with a tankless when you and everyone else has always had unlimited supplies of hot water? what has the manufacturer and sites that support tankless said about your issues? these things must be rigorously examined and thoroughly for people to get the full picture. this is the internet, you don't just look at VOLUME of text to reach a conclusion! so someone please explain how an appliance that draws power to keep X gal. of water hot uses MORE electricity than one that heats the same amount of water the same way but doesn't have to store it! makes absolutely no sense. explain.

Bill,
I have explained it....... Heating water is pure physics. The only debate here is the Return on Investment and Life Cycle Costs....... You will pay nearly $1,000 more in 2008 dollars for a tankless heater. How *long* does it take to get the $1,000 plus lost interest income back in energy savings? Once you get all this back, then you can start talking about how much money you are saving. Until such time as you get that money back, you are Cash Negative.

We are building in the Houston area and are getting to the water heater decision page. A local guy wants $2300 ea to install a Rinnai and we need two. We are only two people, we have a 4000 sf house with 3 full and 3 half baths. Our main water useage will be master bath where we will ahve three shower heads and an air tub. The roman tub filler will supply water at 18 gpm. The kicker to this installation is that we are using Icynene insulation so the attic will be conditioned space, so special venting is required fora tankless and I assume a traditional as well. Is that correct?

Tim,
You need to read the latest column I just wrote about these products. It is being loaded to the website as I type this and is called Tankless Water Heater. What you need to think of as you read it is the size of your family compared to mine.

None of this matters of course if you want continuous hot water at any cost......

You are going to have to adapt your life style to a tankless water heater..
two people cannot take a shower at the same time...

this is a simple --fact of life-- with them...


perhaps if you are alone without a family it wouldwork ok ...but in the real world they will eventually fail you...

please feel free to read the information I have collected on them

http://www.weilhammerplumbing.com/houseofhorrors/

weilhammerplumbing.com

go to the tankless page and read the
information I have collected over the past few years...

if you still want to take a leap of faith and get one of them....
go for it..

go ahead and shoot yourself in the foot.....


anyone who would spend over 2800 each for 2 Rannie tankless heaters to give their new home hot water has got to be absolutely nuts..... you will never ever re-coup your investment ....

Why not just install a 75 gallon gas hot water heater for $1200 and be happy with the saveings??? Put the saved money in the bank and let it draw interest.


Also...dont forget finding a service man 3 years from now to work on them...that is going to be a challenge too...

eventually you are going to need service and then you will realize what everyone is trying to tell you....


weilhammerplumbing.com

Your calculation for the cost of using a tankless heater are incorrect. You said,

"I also timed our hot water usage. On average, hot water runs in our home approximately 90 minutes each day. 50 minutes of that usage is showers, the rest being cooking and cleaning. If I had a large 165,000 Btu tankless heater at my home, it would have consumed 248 cubic feet of gas each day. Doing the math, I arrive at a cost of $1.32 per day using a whole house tankless heater. Unless I am mistaken, it would cost 3.5 times more money to use this heater in my home."

The problem with your calculation is you assume that the tankless heater ALWAYS cranks out 165,000 BTU. That is incorrect. That is the maximum that is will produce depending on the temperature increase it needs to provide and the flow rate.

The bottom line is most tankless are more efficient (some are MUCH more efficient) at heating water than a tank based system.

You do raise some correct points and limitations on tankless systems, but throwing out bogus calculations to show that tankless will cost more does not help your argument any. It is true that tankless can cost more to run, but that is only going to be the case if you actually use more hot water per day.

Matt

Matt,
I stand corrected on that one point. But the bottom line is that people should be very careful about buying one to save money.

I must say after having reading all the letters and e-mails that I am thoroughly confused.

From what I’ve read, there are two main issues. One being energy efficiency and the other is whether the tankless system will actually supply the needed hot water given a families living and usage situation. It seems to me that there is not a definitive answer on either question.

Can a tankless system (in this case electric - not gas) handle the hot water needs of a household with say someone taking a shower while someone else is washing the dishes for however long they wish or even filling a bathtub with enough hot water?

Second, given the same usage as was used with the old style hot water tank system, will this same individual save money over time by “investing” in a tankless hot water system? Again the water usage would be the same.

An additional issue for me would be – how long does the tankless system last? A conventional electric hot water tank will last 6/10 years or so.

I live in a condo building and having to replace hot water tanks regularly is an ongoing concern to all members.

Thanks for your time!!

Dave C.

Dave,
The right-sized heater will satisfy that demand. A conventional storage heater can last much longer than 10 years!! All one has to do is install a new anode rod every 5 years and feed the heater fairly soft water.

Thanks for you quick response.

So in your opinion then a tankless system would work in a condo situation (2 full bathrooms) with multiple uses at the same time? It could handle the supply? That's great. Maybe the association can start recommending them as an alternative to the present tank storage system. The current storage systems are okay but they need replacement frequently. They are constantly bursting and causing severe damage. This may be due to the anodes not EVER being replaced. Our water is extremely hard though and perhaps that is the reason as well.

Any recommendations on electric manufactures for tankless systems you’d recommend?

Thanks again!!

Regards,
Dave C.

David,
You better read all of my columns on this topic. If certain things happen, you may be disappointed with the temperature in periods of high demand. As for the storage tanks bursting, are the plumbers installing expansion tanks? Read my past column about water-heater expansion tanks.

These are great articles, quite a debate. SO, as of April 2008, anything new? I've got 2 plumbers advocating a tank vs tankless solution. A dual Rinnai R94LSI is being proposed vs dual Bradford White 50 gal. Any quick advice? Thanks.

I am not an expert by any means but I do currently have a tankless water heater installed in my "newly" constructed home. We have been in our home for approx. 1 1/2 years. I have not had any problems with the quantity of hot water available. We are in Texas. The thermostat is set for 120 degrees. I'm pretty sure we have low-flow shower heads installed in both bathrooms but definitely not in the tub.
A few months ago my family came in from working outside. My daughter got into the HUGE whirlpool tub in my bathroom (and filled it up). My son got into the shower in their bathroom. My husband got into the (separate) shower area in our bathroom. All at the the same time. I was washing dishes in the kitchen waiting for a bathroom to be clear. Everyone had wonderfully hot water. The water at the kitchen sink was not quite as warm as I wanted it to be, but it wasn't cold by any means. Everyone was able to get clean (without waiting for the hot water heater to get the water warm again) and we were able to do it all within about 30 minutes. We would not have been able to do this in our old house without someone having to "enjoy" a cold shower at some point. That alone was worth the extra we paid for the tankless.
We paid $850 for the water heater when we were building and it didn't cost us any extra to install it since something had to be installed either way.
Our tankless heater is an outdoor propane 7.4xp by Richmond. Our water bill is not really any higher than it was at our old house (just across the street and down a ways) since we all take the same number of showers (although they were probably much shorter when the water turned cold). I have only used a total of 200 gallons of propane since we moved in and I have a stove and an extra oven that are both gas which we use a lot since we love to cook around our house.
I feel that our tankless water heater was a wonderful investment for our family and it really is pretty nice after a long day of working in the garden to not have to worry about hurrying through a shower just so the cold water doesn't hit!

where can I get the gas valve bosch aquastar for a tankless water heater. I have search on bosch website and it seems impossible to get to them. my emial is gotyourhouse@hotmai.com model 8 707 021 090 ng

@Lew

I know this post is old, but I've recently purchased a brand spanking new Takagi gas system. It would have been wonderful, I'm sure, if I wouldn't need a massive service upgrade to install it. After speaking with Takagi support, it appears that my 70K BTU/HR line will not be even close to enough to power the bugger to anything above 95F on a 2 GPM shower head, let alone a 4GPM tub faucet.

If you decide to go with an electric model, you'll be pulling 100A at 240V, much more then (likely) your current electric model. If you decide to go with a gas one, make sure you have at least 7"WC gas pressure, and a 3/4" gas feed to your heater.

Hope that helps.

I have to scratch my head a little. I installed a Rinnai R75LSi natural gas unit just about two months ago. I just received my September natural gas bill. At the meter last year for this month I used 17 therms. This year I used 11. If you include the billing factors, last year I used 16 therms, this year I used 12 therms. That gives me a 25% savings (12/16). Thus far, looking at my meter, I am on track for another 25% savings this month.

Remember too that tankless hot water heaters have a modulating gas usage. Yes, the tankless heater might do 200,000 BTUs, but it does not do that all of the time. For example, at 2.5 gpm it might only use 50,000 BTU, 4 gpm 100,000 BTU, etc. It will only use the amount of natural gas that it needs to heat the water. It does not run at full throttle the whole time, only if the demand says so.

I have 3 showers. I have run at 3 simultaneously. No one knew the wiser.

Hi we live in Tacoma Washington and I don't know the average tempeture water here,but we just purchased a Bosch 250SX and paid $1000 and something dollars and now we are being told it might cost two more grands to install the nature gas tankless water heater. Do you think ist worth it for a family of two..at this point we have no choice as we have had the tank for a yr and lowes will not take it back and our electric water heater has rust coming out of it,,the installer suggested to get a Rannai LS 2800. Isn't this the same heater with a different name?..

Aaron Meier, who installed your Takagi? Was it an authorized Takagi installer? If your gas line and/or pressure was undersized, they should have picked up on that right away. Tankless water heaters do have specific gas needs. Remember though, it does not use all of that gas at a time, it only uses what it needs.

Joe Delgado, I would go to Rinnai's web site and look for authorized Rinnai installers in your area. If you Google them, you will find them and their web site. From there you can just enter your zip code and you will get a good list of recommended installers. They should be able to get you on the right track.

I'd like your thoughts on how to make a calculation on the energy saved (if any).

I have two electric water heaters connected in series. I am considering replacing one of them with an electric tankless water heater(Bosch AE125).

I'm thinking of keeping the tank water heater at 90 degrees, then connecting it to the tankless set at 122 degrees.

Bosch estimates that the flow rate at the 4.4 gallons per minute at a 35 degree rise (90 to 125). Which seems reasonable, but Bosch only provides an estimate of average operating costs under normal usage.

I live in the deep south, and have looked at this as a solution. We are in a position to install outside, and rise in temperature is minimal from summer to winter. The only way I see this helping my household is that there are only the 2 of us, and I am out of town 4 days a week....

Install costs for traditional water heaters seem to be mostly ignored in this column while the install costs for tankless systems are highlighted as a negative. While the install costs for a tankless system may be more expensive than with a traditional system, these costs are not inconsequential by any stretch- installation may end up being close to the cost of the heater or even exceeding it in some cases. While I appreciate the information contained here, I find this omission somewhat misleading.

Tim,
In my area natural gas is not available, and my conventional water heater is electric. Electricity is $0.20/kwh (renewable sources). I have a propane tank for the generator, and pay $85/yr low-usage fee. House is ~1800 sq. ft with 2 baths.
Any thoughts on whether a tankless makes sense in my case?
Thanks

propane tankless, that is.

Many factors come in to play when dealing with tankless. One comment I have seen on a few posts talks about having 2 different temps at different points of service. This is a problem of the plumbing, for it is impossible for the unit to create 2 different temps. Another is the assumption that 2 2.5 gallon per min rated showers canot run at the same time. This again is untrue a 2.5 gallon per min showerhead is calcualted at 80PSI I doubt anyone here can say they havce 80 PSI Plus your blending hot and cold together. retrofit work truly requires a knowlagable contractor. New construction gives you the best oportunity to take advantage of this technology becouse you can engeneer the plumbing so much better with pex lines. Please use the resourses that are available thru foreverhotwater.com and the manufacturer of at least Rinnai you can call on the phone directly.

Your article on tankless hot water heaters has been enlightening. I live in South Western Michigan and would like your recommendations for a new hot water heater. Presently installed is a 40gal. electric unit. I live in the country and use propane for heating and cooking only.

I own a Adtec 44A electric tankless water heater. I absolutely love it! Adtec Systems is a local company in Olympia and that is where they manufacture 6 different electric tankless heaters. I've had it installed in my house for the past 2 months and I've cut down 40% on my energy bill! I recomend visiting their website if you are in the market for a electric tankless water heater http://www.AdtecTankless.com. Customer service is awesome, very helpful and nice when you ask dumb questions (I tend to do that alot). Anyways, I will never go back to a conventional hot water tank.

I understand that if one's hot water demands exceed the capability of the tankless water heater, then the water will not be heated up to the desired temperature. That is bad for things that must have hot water of a certain temperature, like dishwashers.

However, couldn't that shortcoming be minimized by installing a flow regulator on either the incoming or outgoing water to the water heater?

Since it would reduce the hot water flow rate when too much is demanded, rather than providing lukewarm water, it wouldn't be any different when you are washing your hands or taking a shower, but a dishwasher or washing machine that needs water of a certain temperature would get water of the desired temperature, it would just take a little longer to get it.

Are there any gotchas I'm overlooking here? I'm actually surprised flow regulators aren't built in for just this reason, I always thought that's how they'd work until I did a little research on them.

Am a Professional Engineer investigating water heaters. This looks like a great resource for field experience.

I read that one thing that makes a tankless hot water heater more fuel-efficient is that they are "fully modulating". In other words they only use the fuel needed to heat the water to the set point at the current flow rate. If you are washing your hands using under 1 gallon per minute (GPM) you will be at a lower firing rate than you would be if you are filling your tub at 3 GPM. Have you taken into account this ino your calculations. What would be the consequences?

Also I hear that changing to a tankless water heater is not worth it if you are going to change from a 50-gallon gas heater to a tankless you are probably not going to realize quite that much energy savings. In fact a 50-gallon tank water heater does not use much more fuel at all compared to most tankless heaters.

Is this right?

I installed a Bosch 250 several years ago when I lived in the San Diego area. I was not very happy with it pretty much from the beginning.
1. When taking a shower, I never could reduce the flow of hot water to the flow I had always used with a tank heater, the Bosch would just shut down and then I had a cold shower all of a sudden.
2. Whenever there was a little too much wind, the pilot would blow out, never had that problem with the tank in the same outdoor closet.
3. You need to have specific maintenance done every year or so. So much for saving gas, you just spent it on a plumber.
4. A part wore out and I ordered replacments. When I tried to install them, the design of the Bosch was so bad that the hidden screws could not be removed with out breaking them due to the corrosion. The tankless heater was now unusable. And to top it off, the parts were non-returnable even though they were still in the sealed bag.
5. Went right out, bought a 12 year warranty tank, the tankless really only had a 6 yr warranty, and was never happier.

Tankless water heaters are for people who have money to burn, literally.

I forgot a point. The modulating of the heat doesn't work all that well. My house then had the water pipes in the roof and the outdoor pipes buried under the driveway. So for the first few minutes, my shower was pretty good, then as the cold water came up from the street I would have to readjust the temperature of my shower several times to keep it the same. And the settings between hot & cold valves during the summer were much different than winter. With a tank, I could turn both valves to the same position every time without wasting a lot of water.

2007 was a while back, it's now March 2009 with more efficient technologies like the Noritz 0841 with a 93% efficiency level! With a stainless steel and copper dual heat exchanger.

There's a 30% Federal tax credit for the purchase & installation.

And rebates from local power companies:
http://www.dsireusa.org/

Cash Rebates from Energy Star:
http://www.energystar.gov/index.cfm?fuseaction=rebate.rebate_locator

Enter your zip code

Scroll down to:
"Residential Water Heaters"

Check the box:
"Whole-Home Gas Tankless"

Click on:
"Locate Special Offers/Rebates"

Here's some great unbiased honest info:

Tankless 101

A tutorial for the homeowner and the professional

http://www.profitableplumbing.com/_wsn/page5.html

S.E.T.S., American Tankless, and now EcoSmart. All these electric tankless hot water heater companies are one and the same, a progression (and I use the term only in regards to time) by the same people. Beware! I spent $789 on an American Tankless in spring 2008. The heater does not work and it is impossible to get in touch with American Tankless now, despite the "lifetime warranty" I was promised. I am now going with Stiebel-Eltron, a tried and true German company. Beware the website <ecosmartus.com>. It sounds great, as did the previous American Tankless website, but it is the very hype that cost me $789 for nothing.

i'm a plumbing contractor in Calif. and still have a bit of a problem installing Tankless Water Heaters. Actually, I haven't sold or installed one yet. Its not that I don't want to, its a great job for income. But, I'm not doing my customers any favors by installing something that cost roughly 3 times more that a storage type water heater, cost savings in energy just don't happen. Remember most all tankless water heaters require a 3/4" gas line(natural). Storage type water heaters(most) require a 1/2" gas supply line. Also, something very important for consumers to think about with a tankless water heater is maintenance, something completely not mentioned in almost every article about tankless water heaters. My last discussion with a rep. from Renai Tankless was that they have a chemical that has to be installed in the hot and cold sides of actually heater to eliminate any corrosion that builds up in the tubes that flow back and forth with the unit, also try to get the unit repaired if there is a problem with the electical part of the unit, you may go days without hot water and I've had two customers looking for parts and I couldn't get them any faster than the customer could !!!! My two cents is : Its a great idea, but right now, the way they are built, I'll continue installing storage tank type and keep my customers happy.

Hello,
I own an AdTec Tankless water heater, model 44a. I purchased it in April of 2009. It's been working great for 3 months. Now no hot water. Called AdTec, no answer and no replies to e-mails.
Does anyone know where to get this thing fixed? Please help!
Thanks.

I recently had a tankless water heater installed. It has created a problem with the old single valve shower faucets. We get only luke warm water out of the shower head. All other faucets have two valve styles and the hot water has good pressure and is very hot. I tried to reduce the cold water pressure with a valve, this helped but still not able to get hot enough. Is a new replacement shower valve or other fix to handle difference in water pressures.