# tankless water heaters - what do you think? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [November 25, 2014, 4:07pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602 "2014-11-25T16:07:37Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![Habeed](https://avatars.discourse-cdn.com/v4/letter/h/a587f6/32.png) [@Habeed](https://boards.straightdope.com/u/Habeed)\ **Post date:** [November 26, 2014, 11:13am UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/41 "2014-11-26T11:13:41Z")
> [@Waterman](#): > > This is a little misleading in the sense that while electricity may be 95% efficient it is being measured at the outlet (plug). The steam electric generation process (used for the vast amount of generation in the US) has an overall energy efficiency typically in the 33-38% range with the very best approaching 45-48% (see Carnot cycle on Wiki for more info). Actually, it’s 54%+ : Google for “[combined cycle](http://en.wikipedia.org/wiki/Combined_cycle)” on wikipedia. Essentially, you can either burn the natural gas in a tankless heater for about 50-60% efficiency, or you can burn it in the power station at about 55% efficiency then lose about 10% sending it over the transmission line and lose another 5% in the electric tankless heater itself. Natural gas delivery lines leak a little and have higher costs to transfer energy than electric wires. TLDR, it’s very close in terms of real overall efficiency, and the higher upfront cost of buying and installing a natural gas tankless heater means the electric ones may be a better choice. Not to mention, it’s probably a better idea to plumb a house with 3 or so small tankless heaters (such as 1 for master bath, one for second bathroom, one for kitchen/laundry) which means there is some redundancy in the hot water supply and the delay for hot water when turning on the spigot is minimal. ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [November 26, 2014, 11:40am UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/42 "2014-11-26T11:40:36Z")
Over here in the UK, what you call ‘tankless heaters’ and we call ‘combination boilers’ are pretty universal in new builds and as replacements. Of course we tend to have smaller houses without basements, so the imperatives are different. I had a new boiler installed recently because the old one (also a combo) was 15 years old and leaking. The old one was in my garage and it took forever to get hot water to the tap, so the new one is in the kitchen, on the wall near the sink. This also happens to be directly under the bathroom too, so the pipe runs are short and hot water is there within a few seconds. The boiler supplies hot water on demand and runs eight radiators. The total cost to me, including the water and gas feeds, was under £3000. I don’t really understand the problem of the gas feed as all gas pipes here are ½" (now 12mm). This is ample. ---
**Author:** ![Digital\_is\_the\_new\_Analog](https://avatars.discourse-cdn.com/v4/letter/d/a88e4f/32.png) [@Digital\_is\_the\_new\_Analog](https://boards.straightdope.com/u/Digital_is_the_new_Analog)\ **Post date:** [November 26, 2014, 1:19pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/43 "2014-11-26T13:19:24Z")
> [@Khendrask](#): > > I just replaced my electric tank heater after 24 years, it wasn’t leaking, and the only issue I ever had with it was a need to change the $18 heating element twice. The new one is much better insulated, and glass lined, so the efficiency is up, and tank corrosion is even less of a concern. For me, the cost would have been about $800 for the water heater, and then another $2000 or so just for the electric service. The tank heater cost about $325 with a 20 year guarantee. Easy bet there. I suspect it wasn’t dramatic, but do you have any indication of how much you save on the monthly electric bill after installing the new tank? As I mentioned above, I’m in a similar time frame on my heater. Just curious what I might expect if I decide to proactively swap it out. ---
**Author:** ![Muffin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/muffin/32/4341_2.png) [@Muffin](https://boards.straightdope.com/u/Muffin)\ **Post date:** [November 26, 2014, 1:29pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/44 "2014-11-26T13:29:14Z")
[National Energy water-heater firm fined $7M for sales practices](http://www.cbc.ca/news/business/national-energy-water-heater-firm-fined-7m-for-sales-practices-1.2849075) ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [November 26, 2014, 2:22pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/45 "2014-11-26T14:22:08Z")
> [@Muffin](#): > > [She’s double billed for a year after switching water heaters: Roseman](http://www.thestar.com/business/personal_finance/2013/02/01/shes_double_billed_for_a_year_after_switching_water_heaters_roseman.html) > > [Ontario cracks down on door-to-door water heater sales](http://www.thestar.com/news/queenspark/2013/04/11/ontario_cracks_down_on_doortodoor_water_heater_sales.html) > > [Government of Ontario on door-to-door hot water scams.](https://www.ontario.ca/consumers/door-door-sales-and-home-service-contracts) Ah, so it’s actually _criminal_. Don’t run, call the appropriate state agency and report these people. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [November 26, 2014, 2:31pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/46 "2014-11-26T14:31:56Z")
> [@Waterman](#): > > > [@blood63](#): > > > > The total cost over ten years is about $5300. That’s payments of $44 over 120 months. > > Yes, that 10% does make one shudder. > > Sorry, but your math is wrong. As stated earlier, the interest on a 10-year, 10% APR, $5000 loan is $2,929.04 (using Excel PMT formula so it differs slightly from previous value). The payments are $66.08 per month for 120 months. It sounds like the OP is saying that the actual cost for the water heater is something less than $5,000 but that the total paid out after ten years is $5,300. ---
**Author:** ![SpeedwayRyan](https://avatars.discourse-cdn.com/v4/letter/s/ce7236/32.png) [@SpeedwayRyan](https://boards.straightdope.com/u/SpeedwayRyan)\ **Post date:** [November 26, 2014, 2:42pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/47 "2014-11-26T14:42:48Z")
Ten years is WAY too long to pay for a car, much less a water heater. If you’re tight on cash, get a new tank-style heater from a REPUTABLE source. If you don’t like the idea of heating water just to let it sit in the tank all day, and you can spend a little more, pop for a tankless…again, from a reputable source. I recently just got a new tank-style water heater, and it was like a few hundred bucks. I would have gone tankless, but we’re not planning on living in the house for much longer. These people are scumbags who prey on people. I don’t buy SHIT from people who show up at my door – I choose who to do business with. You should do the same, or you’ll end up paying more in interest than you should have paid for the water heater. ---
**Author:** ![jtur88](https://avatars.discourse-cdn.com/v4/letter/j/e9c0ed/32.png) [@jtur88](https://boards.straightdope.com/u/jtur88)\ **Post date:** [November 26, 2014, 2:44pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/48 "2014-11-26T14:44:52Z")
In the third word, everybody has a tankless water heater, if they can afford anything at all. Given that, I am amazed at how much they cost in the USA. They are almost all electric, because gas in poor countries comes in kichen LP jugs. I’ve been in quite poor homes, way below “middle class”:, that had tankless water heaters. South American budget hotels have on in every room. They’re electric, and are often pretty scary, and you might get a shower of sparks instead of water. One consideration in the USA would be that you would need a separate tankless in every room where you want hot water, which would be the kitchen and at least one bathroom, so an American house would need two or three of them. And you’d better be accustomed to a showere, because you’re not going to be running a tub-ful from it. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [November 26, 2014, 2:51pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/49 "2014-11-26T14:51:20Z")
How much do you think they cost in the US? ---
**Author:** ![Chefguy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chefguy/32/138_2.png) [@Chefguy](https://boards.straightdope.com/u/Chefguy)\ **Post date:** [November 26, 2014, 3:02pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/50 "2014-11-26T15:02:42Z")
> [@jtur88](#): > > In the third word, everybody has a tankless water heater, if they can afford anything at all. Given that, I am amazed at how much they cost in the USA. They are almost all electric, because gas in poor countries comes in kichen LP jugs. I’ve been in quite poor homes, way below “middle class”:, that had tankless water heaters. South American budget hotels have on in every room. They’re electric, and are often pretty scary, and you might get a shower of sparks instead of water. > > One consideration in the USA would be that you would need a separate tankless in every room where you want hot water, which would be the kitchen and at least one bathroom, so an American house would need two or three of them. And you’d better be accustomed to a showere, because you’re not going to be running a tub-ful from it. The tankless heaters you see overseas are quite small, as they are point-of-use heaters. They typically only measure about 12" x 8" or so and can be had for $150 or so in the US. Tankless heaters for a house in the US are typically much larger (18 x 24 or larger) and much more expensive ($700-$1200). ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [November 26, 2014, 3:02pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/51 "2014-11-26T15:02:53Z")
> [@jtur88](#): > > One consideration in the USA would be that you would need a separate tankless in every room where you want hot water, which would be the kitchen and at least one bathroom, so an American house would need two or three of them. And you’d better be accustomed to a showere, because you’re not going to be running a tub-ful from it. A properly-sized tankless system can supply a whole house easily. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [November 26, 2014, 3:04pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/52 "2014-11-26T15:04:38Z")
He’s talking about the tiny cheapo ones he’s seen in other countries. ---
**Author:** ![Caffeine.addict](https://avatars.discourse-cdn.com/v4/letter/c/f475e1/32.png) [@Caffeine.addict](https://boards.straightdope.com/u/Caffeine.addict)\ **Post date:** [November 26, 2014, 3:05pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/53 "2014-11-26T15:05:57Z")
I had Sears install a gas water heater in my house for about $800 a few years ago. I replaced the water heater in my old house because it was 14 years old and I figured it was time to change it out. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [November 26, 2014, 3:11pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/54 "2014-11-26T15:11:11Z")
> [@Really\_Not\_All\_That\_Bright](#): > > He’s talking about the tiny cheapo ones he’s seen in other countries. Right, I’ve seen those too and I doubt they would meet minimum code requirements in North America. The reason American models are not cheap is because they actually have to work with a reasonable expectation of not killing anyone. ETA: I’m sure economies of scale are also a factor. Tank water heaters have been the default option in the US for a very long time. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [November 26, 2014, 3:13pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/55 "2014-11-26T15:13:40Z")
You burn down one thousand wooden home and people never let you forget it… ---
**Author:** ![Mr.Milton](https://avatars.discourse-cdn.com/v4/letter/m/6bbea6/32.png) [@Mr.Milton](https://boards.straightdope.com/u/Mr.Milton)\ **Post date:** [November 26, 2014, 3:53pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/56 "2014-11-26T15:53:01Z")
Wow! A lot of posts on this one! Prior to relocating ot the US east coast, I lived in Northern CA. The reason for mentioning this is because I was in a place with high mineral content in the water. The water heaters would last 3 to 5 years on average because of this; it caused the heaters to corrode rapidly. I could always telll when the heater was getting towarsds the end of its life when after using a good amount of hot water --such as after a shower-- I would hear a pronounced tapping sound from the heater. I was told this was all the mineral gunk circulating and bouncing about as the heater heated the incoming water. So if your heater makes these noises, it is probably time to check it closely and consider replacement. One thing that is necessary when remmoving and replacing the heaters is to drain the old one first, obviously. With the heaters I had in CA, I could drain the water out but they’d still be heave because the dissolved minerals were still in there and had created a sort of undrainable sludge. I would “walk” the old heaters out into the backyard and tip them over. Most of the goop would them escape, and it was very instructive. Whitish from the minerals and greenish from the dissolved sacrificial anode. It resembled chopped up carpet padding more than anything else. ---
**Author:** ![TruCelt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/trucelt/32/523_2.png) [@TruCelt](https://boards.straightdope.com/u/TruCelt)\ **Post date:** [November 26, 2014, 4:55pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/57 "2014-11-26T16:55:38Z")
> [@jtur88](#): > > In the third word, everybody has a tankless water heater, if they can afford anything at all. Given that, I am amazed at how much they cost in the USA. They are almost all electric, because gas in poor countries comes in kichen LP jugs. I’ve been in quite poor homes, way below “middle class”:, that had tankless water heaters. South American budget hotels have on in every room. They’re electric, and are often pretty scary, and you might get a shower of sparks instead of water. > > One consideration in the USA would be that you would need a separate tankless in every room where you want hot water, which would be the kitchen and at least one bathroom, so an American house would need two or three of them. And you’d better be accustomed to a showere, because you’re not going to be running a tub-ful from it. You are thinking of [these…](http://johnnyvagabond.com/travel-tips/survive-suicide-shower/) We are talking about[these.](http://www.homedepot.com/b/Plumbing-Water-Heaters/N-5yc1vZbqly) ---
**Author:** ![jtur88](https://avatars.discourse-cdn.com/v4/letter/j/e9c0ed/32.png) [@jtur88](https://boards.straightdope.com/u/jtur88)\ **Post date:** [November 26, 2014, 5:42pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/58 "2014-11-26T17:42:06Z")
> [@TruCelt](#): > > You are thinking of [these…](http://johnnyvagabond.com/travel-tips/survive-suicide-shower/) > > We are talking about[these.](http://www.homedepot.com/b/Plumbing-Water-Heaters/N-5yc1vZbqly) At the extreme, yes, but the second type is also common, I had one in my house in Chile. The OP was talking about $5K,and the ones in your link are under $200. By the way, my sister just had a 30-gallon tank put in, paid $600 installed. She said the hardware was $400, so I think she got ripped off for labor. ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [November 26, 2014, 5:51pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/59 "2014-11-26T17:51:38Z")
They don’t cost $5K here. The OP is being scammed. ---
**Author:** ![blood63](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@blood63](https://boards.straightdope.com/u/blood63)\ **Post date:** [November 26, 2014, 6:31pm UTC](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602/60 "2014-11-26T18:31:26Z")
> [@Waterman](#): > > Sorry, but your math is wrong. As stated earlier, the interest on a 10-year, 10% APR, $5000 loan is $2,929.04 (using Excel PMT formula so it differs slightly from previous value). The payments are $66.08 per month for 120 months. Yes, if my loan were $5000 but my loan is not. Clearly the company wants me to buy into their 10% payment plan because they said nothing about an up front cost. Their plan is $44 a month for 120 months. The total after 10 years is 44x120 or about $5000. Can anyone calculate the actual 2014 cost of equipment and installation from this? [Previous page](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602.md?page=2) [Next page](https://boards.straightdope.com/t/tankless-water-heaters-what-do-you-think/705602.md?page=4)