Care to share your experience with a tankless hot water heater?

[laundry_queen]

I'm moving into a new place tomorrow that has this. It also has a nifty new kind of furnace that uses the heat from the hot water that circulates to heat the house (and the forced air fan uses 50% less energy than conventional gas furnaces). I've heard some bad stories, however, about this type of heater not being able to meet hot water demand and needing a lot of expensive maintenance in areas with harder water, so I thought I'd ask here if anyone had any experience with the tankless system?

I'm pretty excited about living in this new energy efficient house, but don't be afraid to burst my bubble. I want honesty

[hollysmom]

1. H,mmm My old kind of furnace used to do that

Was a real pain because the furnace would run all summer and cost us a fortune in fuel. And heat the house more.

[FBaggins]

2. Had one for about three years now and LOVE it.

Never run out of hot water - even when family visits. Can handle up to three showers at the same time. Reduced our gas bill by about $15.

And they're supposed to last twice as long, so in the end it should actually be cheaper.

Most of the challenges shouldn't impact you since it's already installed. They can be VERY expensive to install if you don't already have a large enough gas service... or need a new chimney or lots of plumbing. Ours is an exterior model, so it's self-venting and went in right next to our gas service (and saved space).

It can add a few seconds to the time it takes to get hot water at a faucet. For some people (especially on older models), there's a "cold water sandwich" effect that can be annoying. You get out of the shower and a couple minutes later someone else gets in and turns it on. The water in the pipes is already hot, so she gets right in. But the tankless was off and takes a couple seconds to kick back in... all while cold water runs through it. So you get a "sandwich" in the pipes of hot-cold-hot that hits her in the shower.

We've never run into it. The newer models kick in much faster if they've recently been on... and a clever installer can mitigate the problem with a small mixing tank.

Whether or not it can meet demand depends entirely on the size of the unit and that of your family. But it will never run out of water, so the worst case is taking turns.

The "expensive maintenance" can be done yourself if you're reasonably handy. You buy a 5-gallon bucket and a few gallons of white vinegar. You get a submersible pump and a couple lengths of hose (match up the inlet/outlet taps on the unit - they're probably standard hose fittings... so I used an old garden hose)... then you just cut off the water supply and drain the unit (turn a couple valves) and run vinegar through it for 30-60 minutes. Do that once or twice a year and you shouldn't have problems for decades. If you don't do it, you'll get less and less hot water from the unit and waste fuel (which may be why some people get less hot water than they expected).

After the initial outlay for pump/etc, it costs you a few dollars a year in vinegar and a couple hours of your time.

Best of luck!

[happyslug]

3. Used one for 40 years, no problems

Now, the first one I used was from the 1920s, had some problems with water flow, it only had one flow and in the 1920s it was much lower then modern shower use, thus was on the slow side. On the other hand I never ran out of hot water, no matter how much I used. Had to replaced the internals in the 1970s (had to find someone who could turn copper pipe to fit inside the old RUUD heater), but then it lasted another 20 years.

Finally had to replace it, it was just to old, not only was the pipes going (in the 1970s I had only replaced 1/3 of the pipes) but heating element and I needed higher amounts of Hot water (and I question it it meet modern plumbing codes, it was old). Ended up buying a new one that lasted about 15 years, more efficient then the old RUUD, and mounted on the wall so freed up some basement space for other uses. It paid for itself but 15 years it had a Major break in parts (and pipes) and I had to replace it last December, no problems since.

Here is a picture the same type of RUUD tankless water heater I use to have:

http://www.google.com/imgres?imgurl=&imgrefurl=http://www.smarterhotwater.com/news_events/vintage.html&h=324&w=432&sz=37&tbnid=hK4OjjE6Y8rZ0M:&tbnh=90&tbnw=120&zoom=1&usg=__6FbUAZR6WdwPLWHBG5L-NhRia28=&docid=4EN3FqHGlluhyM&hl=en&sa=X&ei=PutQUYjZHozs8gT_gYGwDw&ved=0CE4Q9QEwBQ&dur=482

[laundry_queen]

4. Thanks all

So far, so good. I did notice it takes longer to get hot water to where you want it to go...and I had to crank the setting. We had it on the factory setting at first and even at the hottest setting the shower was still cold. I was going to have a meltdown when I figured out how to turn up the temp, now it's all better. happyslug - that thing is AMAZING looking. Mine looks more like this one (except with more pipes as there is hot water going to the furnace):



FBaggins - thanks for sharing your experience, especially with cleaning it out. I've been told that I should have a plumber come show me how to run the solution through the first time and then after that I can do it on my own but there's a 'kit' I'm supposed to buy every year. It would be nice to use vingear instead. Mine has a filter that has to be emptied every week at first, then every month for the first year.

So...I like it so far! We'll see how much it affects my gas bill when i get my first bill in a few weeks.

[Thor_MN]

13. The person that plumbed that needs to invest in some sheet aluminum.

They torched the heck out of the drywall....

[BlueToTheBone]

5. I loved mine. If you find that

the water is fluctuating hot and cold, turn the flow down until it remains hot. You can't imagine a bath that never runs cold! I have a filter on my new house and am getting ready to install my 2 bath heater.

[Kaleva]

6. I don't care for them but that's my own opinion

I prefer things simple and a 40 gallon natural gas water heater with a standing pilot is about as simple a water heater as one can get. As the pilot flame alone produces enough hot water for me, it's cheap to use.

My experience with tankless is that they are quite reliable but are hard to work on when needed. A few years ago I spent a couple of hours working on one where a dead fly was the cause of the problem. It had lodged itself in front of an orifice. About an hour to disassemble the water heater to find the problem and another hour to put it back together again and test. Pretty expensive fly.

A few, with kids, who had them installed found their water bill to go way up as the kids then took very, very long showers whereas before they didn't because they'd run out of hot water with the previous water heater.

[laundry_queen]

7. HA! I can totally see that last thing being a big problem with my oldest.

So far, it hasn't been to big of an issue as she has started showering in the morning so has to get out or she'll be late for school. HOWEVER - it may become an issue this summer. So far, my first water bill was 'normal' - not too high compared with my regular bill. However, considering I have a front loading washer now, and 4L flush toilets, it was a bit disappointing. I'm assuming that the extra time the water needs to run to get the hot water to kick in is really wasteful. You'd think there was a way to have a hybrid system.

[progressoid]

10. Heh, I used to turn off the water when my daughter would take her super long showers.

I'd give her a couple warnings first and just shut it off for a few seconds to give her a not-so-subtle hint that it was time to get out.

[Sherman A1]

8. This is what I want when it is time to

replace my current water heater. Just makes sense to me.

[MADem]

9. I had one when I lived in the middle east, many years ago, and it was wonderful.

It ran on propane, the water went through a little snake of coils that were heated by the gas flame, and b the time the water came out the other end it was nice and hot. Of course, it didn't get super cold over there, so I don't know how they'd work in a New England environment, where I live now.

I've used them in the Carribbean too, but we never had need for very hot water there. I thought the ones in the Middle East were better quality than the Carribean ones, which, I think, were electric.

I had an "electric shower" in UK, that worked good, too--made me nervous, frankly, which sped up my showers--I just didn't like the idea of the water and the electricity so close together!

Of all methods, I liked the propane/gas one the best. The flame came on when you turned the hot water on, and went off when the water stopped flowing through the pipe.

[joeunderdog]

11. Any idea what brand is the best one to buy for a US install?

We're building a modular and would like to use a tankless HW heater. Likely will go propane and solar for heat/elec.

Any help appreciated.

[MADem]

12. Not a clue, sorry. Mine was Persian or from somewhere in the region, and VERY basic.

It was a white box and hung on my kitchen wall. I hooked the propane tank to it, and when I turned on the heater (first by turning the knob to open the propane bottle, then pushing a big clunky button to ignite the flame) it would fire up the pilot (you could leave the pilot going, but it wasted fuel and we had to lug those propane tanks home). The flame would ignite when water ran through the system. The water went through a "series of tubes" that were made of metal, and hairpin-looped back and forth above the flame. The metal heated the water, nice and hot, too!

I do think, if you live in an area where it gets cold and your groundwater is very cool, that you want gas or propane to heat your water as the electric powered heaters or even a solar system might not get the water warm enough year round.

I have heard (anecdotally) good things about Rheem, but that's not first-hand.