Water heater experts give tips, debate tankless

What routine maintenance should I perform on my water heater?

Cochran: You should drain it once every year or two to get the sludge out of the bottom. You should also replace the thermocouple [temperature sensor] every year or two.

Woods: Your owner's manual is the best source of information. Some manufacturers make specific maintenance tasks a condition of warranty replacement.

Davis: You should flush it once a year, twice a year if you have a water softener. You should also inspect the anode rod at least once a year.

How can I keep my water heater running properly and efficiently?

Jolly: Flush it out annually by opening the valve at the bottom of the tank to clear it of any debris.

Knochelmann: By having routine maintenance performed. You need to keep the burner assembly clean, and flush the heater at least once every two years.

What are the pros and cons of tankless water heaters?

Cochran: They're pretty effective. The big drawback is cost. You also want to make sure the company installing it knows what they're talking about.

Woods: They're more efficient and will never run out of hot water. However, initial investment is higher than some people expect.

Davis: In my opinion, it takes up less space, but it requires more maintenance and costs three times as much to install.

What are the most common kinds of water heaters?

Cochran: Most of them are gas. We see a few electric. Tankless water heaters are a big thing right now.

Davis: Natural gas water heaters are about 75 percent of what we see. Power vented heaters are 20 percent, plus a few electric.

How do I know when I need to have my water heater serviced?

Jolly: When the homeowner notices a shortage of hot water, or when there is any leakage.

Knochelmann: Most people do not have their water heater serviced until something is wrong. Routine maintenance helps prevent future breakdowns.

What causes smelly water?

Knochelmann: It is bacteria in the water that reacts with magnesium and aluminum, which produces hydrogen sulfide gas, making water stink.

Jolly: In most cases, smelly water from the water heater is caused by a rotten anode rod. The anode rod can be replaced from the top of the tank.

How much should I expect to pay for a new water heater?

Cochran: A gas-fired tank water heater runs about $700 to $750 installed, plus permit cost. Tankless water heaters run between $3,000 and $4,500.

Woods: It varies by size and specifics, but a standard tank-style heater should run between $600 and $1,000. A power vent-style heater may be in the $1,300-$1,700 range. A tankless gas water heater could run $2,500 to $3,000.

What should I look for in a new water heater?

Jolly: Homeowners should look for an energy-saving model with at least a six-year warranty on the tank and two-year warranty on the parts.

Knochelmann: Energy Star and "green" options, such as tankless gas or heat pump water heaters. Rebates of up to $1,500 are available for each.

Any other pieces of advice you'd like to share?

Cochran: Most water heaters come with a six-year tank and parts warranty and a one-year labor warranty. You're not guaranteed to have a labor warranty, but it's pretty common.

Woods: "Universal" repair parts are a thing of the past. If you're having water heater troubles, be sure to inform the repair company of your model and serial number.

Davis: Make sure your heater can handle the demand. When people remodel bathrooms or kitchens and add new fixtures that draw hot water, they don't always take into account the increased draw on the heater.

Jolly: If the water heater is more than 8 years old, consider replacing it rather than making a repair. A water heater must be installed by a licensed plumber or the homeowner, both of which require a plumbing permit.


We had the oil company delivering oil 8 or 9 times a year - cost 4,000.00 to 4,500.00 a year. We had an electric water heater installed (60 Gal heater cost 400.00 - installed myself), now the oil man delivers 4 or 5 times a year - cost 2,000.00 to 2,500.00 a year. Our electric bill went up about 50.00 per month or 600.00 a year. Savings about 1,400.00 a year with electric water heater. Water heater was installed in 2007. Still going strong.

We compared all types of hot water systems. Our findings are 1.The tankless hot water system is expensive and oversold as an "energy saving device". In fact the reverse is true. It costs a lot to install up front. Secondly it uses a huge amount of energy to heat the water during demand periods. Third, the cost of operation will keep rising as the fuel costs rise. Last, it still uses fossil fuel. One of the leading engineers in Atlanta installed an evacuated tube solar collector hooked up to a 80 gallon solar tank with electric back up. From March through October he unhooks the elctricity for the tank. From October to March he pays 20 to 25% of what he used to pay to heat the water before solar. With the available federal and state credits and from the savings, his cost was recovered within 26 months. Now you go and figure as to which one you want when there is so much instability in the middle east.

The quality and design of a tankless heater determines competitive performance advantage vs. which units are or are not actively marketed by various retailers, distributor or plumbers in a particular geographic area. Whoever is selling the product says its the best. If you do your homework, you'll find the best technical selection. Then shop the install separately with the help of the maker of the unit.

I just wanted to provide an update on the tankless heater problem I had written about in November with the tank not consistently firing on. The problem has completely self-corrected. I changed no settings, no flow pressure, nothing. The only possible explanation that was suggested here that could explain it is that the outside temp has dropped. If there is a temperature setting on there, then the water coming in is much colder than normal, and this is assuring that the heater fires every time. Will have to post again once summer comes on to let you know if this is truly it, but now I am 100% happy with my tankless heater.

I put in a tankless ELECTRIC water heater for under $400 plus $200 to the installer, and it easily saves $500 per year in electricity. If you want to pay $3,000 for a water heater shop in HOME DEPOT. If you want to pay $400 shop online.

in the state of ohio does the maintenance man who works on my apartment does he need to be certified when installing a hot water tank?

The right way to use a tankless heater with a recirc. system: you HAVE to add a surface-mount Honeywell Aquastat to the equation. This is a thermostat switch that is strapped on near the end of the return line, and is set to turn the pump on when the water temp gets too low, and off when it reaches the desired temp. The flowing water in turn will fire up the heater; you just have to use a big enough pump to exceed the minimum flow requirement for your heater. It also helps - A LOT - to put a small (3-5gal) electric water heater into the line right after the heater; mine is sitting literally under the house on bricks (we have a raised foundation). It doesn't need to be plugged in - it serves merely as a "buffer" tank, and a small heater is actually cheaper than a purpose-built "tank". With the tank in place along with the recirc. pump, you get very uniform temps; without it in a recirc. situation, at a faraway tap you get hot water for a few moments, then cold until the heat exchanger really kicks in and all that cold water sitting between your tap and the heater has emptied out to be replaced by heated water. Adding a buffer tank mitigates the problems that the prior poster with the Bosch complained about. That Lowe's affiliated-plumber needs to learn to think outside the box. For the record, this was worked out by the combined efforts of me, the Rinnai engineers here in the US (who were quite easy to get on the phone) and my plumber, who I hired specifically because he had taken Rinnai's certification class (which I don't think they require anymore, as more and more plumbers have become familiar with this type of heater). Also for the record, my Rinnai is going on 10 years old and has required NO service.

Tankless water heaters work fairly well. I have had one for 2 years. Mine is fired up eclectically based on water flow being above a certain level—basically 3/4 on the tap. I would suggest getting one that does not electricity to fire the burner in case your power goes out. - It takes anywhere between 20-45 seconds for "hot" water to reach the faucet...15ft from the tank. Bosch's suggestion is to insulate the hot water pipes so at least "warm" water will flow right away until the "hot" makes it to faucet. The other suggestion by the Lowes installer was to install a water recalculating pump. However, at that point, you may as well just install a high efficient hot water tank. My original order was from Sears for a Power Vented high efficient hot water tank. The installers came out with the tank and were also Lowes installers and talked me into the Tankless Water Heater. - When use the bathroom, we turn on the hot water so when we finish, the water is hot. Also, be aware that the temperature does vary—sudden cold; but don't adjust anything because you will burn yourself, just wait about 30 seconds and the temperature will level out on its own. Not a pleasant experience when taking a shower. No one else in the house; so it is not like someone else is using the water. I complained to Bosch but they claim it is the city's water pressure...the city says it runs a pressure between 50-60, so it meets the standard set by Bosch. Hope this is helpful to someone. Also, Draw your own conclusions. But I have to say, if you have young kids or elderly that may not be quick enough to react to temperature changes, tankless, at least this brand, is not for you. On the plus side, you can set the hot water temperature between 126 and 140 degrees.

I had a new house built in 2007, and at that time it was difficult to find a plumber who had ever heard of tankless water heaters in my area. I had seen them and used them overseas, so I was comfortable with them. I pushed for and got Rinnai brand, The plumber who ultimately did the install insisted that I put in two. He was not comfortable with the manufacturer's flow rate! With two, an alternator is preferred, and I never put that in. I just unplugged one, and have used only one for 3 years now without any difficulties. The only adjustments we have had to make are 1) We have a high efficiency dish washer, which requires on the spot hot water when it is turned on. We run the tap for a few seconds until the water is hot, then turn the dish washer on. 2) On the second floor, (the hot water heaters are in the basement) the heat time is longer, so the kids have to wait nearly a minute to get hot water, then make their shower temperature adjustments. Soon I will plug in the second water heater and connect the alternator, as it should increase the life of the water heaters. I would buy Rinnai tanklees again, but only one!

ive been installing rinnai for about 6 years now and have used other brands, rinnai is the best unit out there. pinkston plumbing

I liked the idea of only using the hot water from a tank water heater to shower (being sure that the temperature is ideal). No one mentioned the advantage of having 50 gallons of emergency water in the tank if your water goes down or public pipes are damaged. I will always have a tanked water heater.

Tankless water heaters have many merits for the traditional home where the house is unoccupied during the work/school day. This is due to the fact that the homeowner is not having to pay for stand-by heating of their water in a traditional tank style water heater. Tankless are also great for home additions that are built a fair distance from the existing water heater as they will minimize heat loss through the supply pipes. Tankless water heaters make less economic sense when there are occupants in the home all through any given day and they are performing a variety of tasks that include hot water usage such as laundry, dish washing, bathing, etc. Additionally, having tankless water heaters in homes with teenagers have proven to be a potentially expensive proposition – endless hot water means they don’t get out of the shower and not only does your water bill go up but so does your utility bill!

How can a tankless WH work with a recirculating system, since the recirc system will not fire up the WH?

I've had a Rinnai for 6 years and have had no problems at all. The cost isn't as much as has been stated to install, but the savings are incredible. I’ve seen a significant decrease on my propane bill, and the only thing we changed was the water heater. There is no maintenance. I also live in a cold climate, with the added challenge of well water, which can be ice cold coming in. It takes no longer to heat the water in the winter as it does in the summer. My dishwasher and clothes washer both work fine using hot water from the Rinnai and both are energy efficient appliances. There is a lot of misinformation out there about tankless heaters, but take it from someone that has one, they are the best thing ever. I would never go back to an old fashioned water heater again!

@Gene - Your plumber doesn't know anything about physics. It is NOT true that tankless systems are less efficient than systems with a tank. Just the opposite is true. It takes the same number of calories of heat a cup of water in either style heater, but the heat exchanger on a tankless system is more efficient than the one on the system with a tank. The tank system wastes heat because between usage the heat in the water is lost in the plumbing or from the tank itself. Tankless systems are significantly more efficient than the conventional systems. They are used all over Europe and have been for years. Your plumber probably didn't know how to install them, or did not want to do so.

I have a plugged tankless water heater coil embedded in my hot-water heating system boiler. I also have an electric hot water heater fortunately. Any suggestions on how to unplug it?

What about solar water heaters vs tankless?

Most of the problems stated in the remarks on tankless heaters are customer related issues. heaters settings need to be changed, flow restricters removed from Lav faucets, temp adjusted on the remote controls. all manufactures have a 800 help line that can also help the customer. If you installed the heater this year you can get up to $1500 income tax deduction. Get a Wai Wela brand tankless heater and you will be in good hands.

I've heard that tankless water heaters may not work well in hard-water areas. I use water softener. Any thoughts on this?

Amber- tankless needs a minimum water flow- that's why turning on another outlet gets the heater to fire up. Settings can be adjusted on the unit- see your manual. Also- watch out if you have low pressure- if you also have water saving faucets installed, it will reduce the flow and keep the tankless from firing. Simple to fix by turning on another faucet to increase flow, or again check the settings. I have very low pressure, and the water saving faucets (hard not to buy those... they are most models these days). It took lots of fidgeting, but the settings are great now for 2-years, and it works fantastic. We have a small propane tank for the water and stove/oven and have only had to fill it once in the two years!

Tankless water heaters require a new way of thinking about hot water. They have a minimum flow requirement, so reducing your water use to a trickle means you will get no hot water. There's also a 3-7 second delay for the heater to kick on again once it's off due to insufficient flow--another delay in getting hot water to the tap. For situations where there's a long run from the tank to the use, such as for a clothes washer or dishwasher, the delay time for getting hot water might be longer than the duration of the use of the water, such as a spray-rinse in the clothes washer (which is on-off-on-off for just a few seconds each cycle). It's counter-intuitive to what our moms taught us--keep the water on, with lots of flow, even if you're stepping away from the sink to wipe the stove, run the water in the laundry tub to get warm water in the initial wash fill, etc.

Amber- tankless needs a minimum water flow- that's why turning on another outlet gets the heater to fire up. Settings can be adjusted on the unit- see your manual. Also- watch out if you have low pressure- if you also have water saving faucets installed, it will reduce the flow and keep the tankless from firing. Simple to fix by turning on another faucet to increase flow, or again check the settings. I have very low pressure, and the water saving faucets (hard not to buy those... they are most models these days). It took lots of fidgeting, but the settings are great now for 2-years, and it works fantastic. We have a small propane tank for the water and stove/oven and have only had to fill it once in the two years!

I installed a Bosch unit myself in 2002 that I bought from Home Depot for $600. Vent piping another couple of hundred. Be careful of Bosch, as there is not a lot of service companies to choose from in any one area and an upfront cost of $150 to simply check it out. Advantages: Much less costly to run; unlimited hot water. Disadvantages: Sometimes doesn't fire; cannot cut the flow below the minimum required flow rate; few seconds of cold water each time you turn the hot water off and then back on. In all, we love it.

I bought an electric tankless for my mother in law when her small (installed in the crawl space) tank model died. It drew 60 amps and would give plenty of hot water to the kitchen sink, but not for the bathtub. Turned out that although it was advertised as sized for a 2 bedroom home, it couldn't heat enough water to give hot water at the bathtub!

How about a substantive article on geothermal, including cost and pros & cons. This one on tank-less was use-less or worse. We installed one six months ago; gas bill dropped significantly, but have to get used to required minimum flow, delay, etc. Rcvd 2 bids based on Angie’s List, cost around $3000 plus $300 for black iron pipe instead of industry standard but questionable flex gas pipe. No regrets including upcharge for iron pipe. Although I did think it was tacky that the installer – after denying that there was any couponing or discounting – mailed us a $100 coupon for our NEXT tankless water heater.

I once had a tankless hot water heater and was glad to get rid of it even though it cost a bundle. Because I live in a colder area of the country the water entering the heater was always cold and took forever to heat up. My appliance repairmen said that all my new energy efficient appliances would never get hot water in time for the appliances to work correctly

We LOVE our ELECTRIC water heater! We bought ours on-line five years ago and have not regretted it a minute!

Tankless heaters are not new. My father was in the oil/furnace/plumbing business in he '40's. He was always talking about tankless hot water heaters. I think they may have been popular for some time until we were all sold on hot water heaters!

We had just installed two Quietside gas tankless a few weeks ago to a re-hab. We seem to get hot water for a bout five minutes, then it goes ice cold for another five minutes, then hot for the duration. Anyone have any insight? I do not believe this is normal.

The 1st poster (Gene) had a plumber tell him that tankless heaters are less efficient than tank heaters. The guy may be a 30-year veteran plumber, but he apparently flunked physics because he utterly misses the point of these heaters. It takes a LOT of energy to keep 40 or 50 gallons continuously hot, far more than the energy required to heat up just the water one uses at the moment. That is just one of the many reasons that much of the developed world has used these heaters for years and years. I've used a Rinnai tankless, which requires NO vent to the roof like it's competitors because it blows it's exhaust straight out, for ten years now and it's performed flawlessly the entire time. I even incorporated it into a recirculating system, so I have virtually instant hot water at any tap in the house, so my install was trickier. But even then it cost far less than the $3-4.5k that Cochran quotes; even with inflation those are very high numbers. And... getting the heater out of the house gave me space to build an awesome cleaning-gear closet :-)

Leonard thank you for the suggestion. However, due to the fact that this doesn't happen consistently at one tap, and actually can happen at any time on any of the taps or none at all, I don't think it is a flow issue. I hear the gas trying to click on when I first turn on the hot tap, and then maybe 30 seconds go by, and it either sticks on and gets hotter, or it dies out and goes cold.

Amber, Take a look at your water heaters specs and your sink aerator. Problem with some "tankless" is they have a "minimum flow" requirement before they will kick on. If it requires 1.2 gal/min and your sink only flows 1.0 gal/min it may not trigger the heater to come on. Solution: Buy an an aerator for your sink that allows more flow (the low-flow one) may not be working for you.

30 yr pro plumber was at my house to do work on a piping project. I asked for his opinion on tankless heaters. He stated they are more costly to run than conventional heaters because the energy used to heat the water in a tankless is not "saved" like it is with a conventional meaning it takes a large burst of energy to instantly and continually heat whereas once a conventional is at peak, just a matter of maintaining the temp every now and then.

I have a "Superstore" brand stainless steel hot water tank that uses my gas fired furnace to make the hot water. The recovery rate (how fast it makes more hot water) is excellent. I never run out of hot water. It cost me $700 ten years ago. I have a family member that had a whole house tankless system (heat & hot water) and their original system was too small for the demand and only lasted about 5yrs. They have since replaced it with a larger system that now works well.

We have two tankless heaters and we love them. Our plumber Lindsey never installed one before but he knows how to read instructions. We have a small one on our guest house -- two sinks, one shower -- and a larger one on the main house. Ours are hooked up to propane. You need to have the correct size pipes or things will get very expensive. In our case, we had new construction and also extensive remodeling so the tankless systems work very well for us. You can take an "endless" shower if you want! Ours are installed on the outside of the house(s); I don't know if they can be installed inside. We recommend them highly--our cost savings and energy savings have been excellent.

It might be worth considering another option: We decided on an old-style tank model, but make it perform very efficiently by keeping its thermostat set at a level where the water temp. is exactly right for a shower USING HOT WATER ONLY. Due to this low setting (and we do dry our clothes on the line), our monthly gas bill averages $15. If we ever want hotter water, we turn the thermostat up just for a few minutes. Given this monthly cost, it would take a very long time to reach the break-even point for the higher cost of a tankless model.

Just want to clarify my earlier message - the house was bought a year ago, and I think the water heater was installed maybe 3 or 5 years ago. Also, when it doesn't come on the first time, it will never come on if I just leave it running. Basically it tries once, and quits. So doing something else (like turning off, turning on another tap, etc. is essential)

I have a tankless gas powered in the house that I bought a year ago. The space savings is essential because my house is very small with no basement. It is VERY finicky though. For example, there are 2 sinks and 1 shower in my house. On any given day, one or the other sink will not fire heat immediately. It is almost like it is not "catching" the gas on. I try all different things, usually what works is turning on another faucet, like the shower tap, getting that hot, and then going back to the sink I wanted to use and the hot water will be fully available. Weird huh? Anyone else have this problem, and any other suggestions? I've never done maintenance on it, so I may try what they recommend here.

Tankless water heaters have been around for many years. . . mostly in Europe. The biggest problem by far with them is bad installation. You need the correct gas flow and water pressure for the heater to work properly. The maintenance required is basically back-flushing once a year which is a simple homeowner process. Cost on the heaters used to be over $1000.00 and still is for the major brands but whole house heaters water heaters are available for around $450.00 plus installation. . . . about the same cost as a 50 gal tank heater.

We have a tankless WH and love it. We chose a model to fit our house (3 baths, dishwasher and washing machine) and can have any three going at once. The biggest asset for us is never running out of hot water, and not having to schedule showers around each other. Ours was about $2K including moving the gas line. No maintenance except yearly replacing the scale filter (twist off, screw new one on).

Thank you for your comments! To add to the information the interviewed service providers gave on tankless water heaters, please see the related story link for the article "Tankless water heaters: Pros and cons." This article takes a closer look at the advantages and disadvantages of this system.

I agree with the others. Other than stating the tankless are more expensive, no info on how well they actually work. I want the 2 minutes I spent reading this article back.

I agree that article is misleading. Need more info on tankless water heaters. I installed 2 Titan electric tankless and they are working great.

I agree with all above. No info on tankless water heaters and that is what the title said - shame on you.

I agree with the above posters. I read this article because of my interest in tankless hot water heaters. This article provided no insight.

The tankless info is largely "mis" information. I have had a Bosch unit in my house for 10 years with perfect performance and zero maintenance. Cost is closer to $1000 than the numbers listed in the piece. Do your research and yo will be happy.

this doesn't tell you any pros and cons about how the tankless water heater works compared to a tank water heater- information was not helpful.

The article is mislabeled. There is almost no info on tankless water heaters.


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