tankless hotwater heaters

[340fyd]

Good and the bad please. I'm looking to get one of these:

http://www.homedepot.com/p/t/203316...rizontal1-3-_-NA-_-203316214-_-N#.UZDQl50o69I

And was wondering if anybody knows anything about this brand.....and if it's enough water to wash hands. It's just a sink in my shop. Thanks in advance.

Lee

 

[elvee]

Re: tankkess hotwater heaters

I have units similar to that, but smaller, in my garage (one in the downstairs bath, one in the wife's art studio upstairs). Mine are only 30A 115V units. In the summer they are fine and provide hot water. In the winter, when the water temp is lower, they provide decent "warm" water. Since they are installed right under the sinks, you only wait 5 to 10 seconds for the warm water to kick in. Definitely nice to have for hand washing, and they don't eat a bunch of space. I wouldn't use what I have to connect the hose for car washing though.

 

[bgarrett]

Re: tankkess hotwater heaters

Even tho its different, I have a Coleman 'camping' heater that works off a propane tank. It makes water hot enough to hurt and fills my very large whirlpool tub. My hassle is the portable propane tank. Other than that it is great and what a way to camp!

 

[Charles (in GA)]

Re: tankkess hotwater heaters

What kind of amperage do you have in your garage panel (or is it attached to the house and using the house panel) This has listed in the specs, 57 amp draw.

Note also that you have to run water at the rate of at least a quart a minute thru the heater, to get it to turn on. This will require you to run the hot water full blast at the sink to get it running and then turn down the hot water and begin to blend in the cold water to wash your hands. (.25 gal per min seems like a lot)

I keep looking at similar units for my shop sink, to replace the 2.5 gal undersink tank type, and depending on the brand, either find horrible reviews of heaters burning them selves up over and over, or after looking at the performance specs, discover that the temp rise is so poor at a decent flow (full open faucet for filling a bucket) that its unacceptable.

Charles

 

[340fyd]

Re: tankkess hotwater heaters

I changed my 200 amp service over to a 400 amp service so that I could have 200 amp to the shop.

I put a 40 slot 200 amp box in the shop so I shouldn't have issues with that, but still I appreciate you pointing that out cause that would definitely be a problem with a smaller service.

See that's the kind of stuff I'm after as far as will it last & does it work for what people are needing to do. Thanks again for the feed back.

 

[Charles (in GA)]

Re: tankkess hotwater heaters

It kinda hinges on what you do with the water. I fill buckets to wash the car, and I Wash shop rags about twice a year, essentially by hand using buckets of hot water. I want to be able to fill a bucket with scalding hot water as fast as the faucet allows.

Present situation works OK, I have a 2.5 gal tank water heater under the sink, set about as hot as you can get it without popping off the TPR valve. This gives me enough hot water to wash hands with, wash my face after mowing, etc, or for filling buckets, it works OK. I would prefer to have a 4 gal unit, but am not inclined to spend the money to replace a good working unit right now.

Water heater is the blue box under the sink. It is a Titan brand unit, made in Italy.

I have looked at various instant units like you are looking at. Price just drives me away. Rheem has some well priced units, but I found several scary reviews on them and can only hope that they have resolved their problems (they would turn on for no apparent reason, bad flow switch possibly, and boil non moving water in the unit till it burned up).

I was looking at units in the 11K watt range as for me, the flow and temp rise for a given flow (they have charts of this available for most mfgs) was acceptable and I too have enough power to make it work.

HD has an Ariston 4 gal under counter that would fit in the area where my 2.5 gal is now but for $229 I hesitate to spend the money. These small units have a good recovery time.

Charles

 

[duc916]

Re: tankkess hotwater heaters

I have one for my house ( 10 years) and my shop ( 4 years). They work great, if you get the correct one. Look at the gpm @ temp rise, not just the "whole home" versions. I have a CPO bosch in my shop and it works great. Shop around as the prices vary for the same unit.

 

[Eagle Point]

Re: tankkess hotwater heaters

I bought the Ariston 110v model from Home Depot for my previous home and it worked great for washing hands, filling buckets to wash cars, basic cleaning of odds/ends. For that purpose it is fine.

 

[bdamico]

Re: tankkess hotwater heaters

wasn't there a whole thread where someone went off about calling it a "hot water heater"?

 

[Highbeam]

Re: tankkess hotwater heaters

Well, most often, the water you are heating is already quite hot so "hot water heater" is a fairly accurate term. Water heater is better.

 

[gringowillie]

Re: tankkess hotwater heaters

I have a Takagi LPG model and have loved it for 8 years . The only drawbwck we have experienced that the electric model is hard water,it is the absolute enemy of our heater .

 

[gringowillie]

Re: tankkess hotwater heaters

That the electric model may share is what I meant to say

 

[CNGsaves]

Re: tankkess hotwater heaters

Curious if any of these small HWH would work with gravity feed? I'd like to have sink in detached garage that is fed by elevated barrel of water.

Any minimum pressure that is needed for tankless versus tank style??

 

[justsam]

Re: tankkess hotwater heaters

No experience with that type unit, but I am a big supporter of the small tank units.

I have a 6 gallon unit under my sink, and it works well for my uses which is to have warm water to wash hands, and to occasionally fill a 5 gal or other mop bucket with hot water.

Looking at that unit, the electrical would be no small undertaking. If it draws 57 Amps at 220V, I wonder what it draws at 240V? You are talking some heavy wiring here. Also it says the element is 8 KW, that leaves about another 5KW going somewhere. Does not seem too efficient.

 

[AV tinker er]

Re: tankkess hotwater heaters

They have been used in Europe for years, I had one in my apartment while stationed in Italy. I have read that they take to long to recoup the cost of purchase compared to a tank water heater. How many people are living in your house, the more people living there the more sense it makes.

 

[Highbeam]

Re: tankkess hotwater heaters

If it draws 57 Amps at 220V, I wonder what it draws at 240V? You are talking some heavy wiring here.

Don't get too hung up on that. Lots of people use 220/240 interchangably.

 

[pmiranda]

Re: tankkess hotwater heaters

No experience with that particular unit, but for handwashing I've seen a couple commercial installations of these paired with touchless faucets that worked fantastically well. Just put your hands under and go. Since those faucets are off/on and low-flow, there's no worry about the flow rate adjustment once installed.

 

[Charles (in GA)]

Re: tankkess hotwater heaters

If it draws 57 Amps at 220V, I wonder what it draws at 240V? You are talking some heavy wiring here. Also it says the element is 8 KW, that leaves about another 5KW going somewhere. Does not seem too efficient.

As voltage increases, the amperage drops off for a given load. NEC limits water heating to 60 amp max circuits, same as electric heating. If you need more wattage, you have to run more than one 60 amp circuit and have separate elements. The larger instant water heaters do just this, two 40 or two 60 amp 240v circuits to make them work.

Something seemed wrong with the 57 amp they gave in the specs, but I could not figure out what.

Charles

 

[justsam]

Re: tankkess hotwater heaters

In regard to drawing more current at 240 as opposed to 220, perhaps I was oversimplifying. I made the assumption that the load (heating element) is pretty much pure resistive and somewhat linear, and therefore current would increase as voltage went up, once past in-rush current. Perhaps there are voltage taps?

I am learning something from this thread in that I never knew there were high power electric versions of tank less heaters. Both my main and guest house have natural gas tank less, and for the small home work great, not so much for the larger home in terms of delay for water, in spite of having a circulation pump.

How do the delivered BTU on these units compare to their gas brethren?

 

[mikec35]

Re: tankkess hotwater heaters

It kinda hinges on what you do with the water. I fill buckets to wash the car, and I Wash shop rags about twice a year, essentially by hand using buckets of hot water. I want to be able to fill a bucket with scalding hot water as fast as the faucet allows.

Present situation works OK, I have a 2.5 gal tank water heater under the sink, set about as hot as you can get it without popping off the TPR valve. This gives me enough hot water to wash hands with, wash my face after mowing, etc, or for filling buckets, it works OK. I would prefer to have a 4 gal unit, but am not inclined to spend the money to replace a good working unit right now.

Water heater is the blue box under the sink. It is a Titan brand unit, made in Italy.

I have looked at various instant units like you are looking at. Price just drives me away. Rheem has some well priced units, but I found several scary reviews on them and can only hope that they have resolved their problems (they would turn on for no apparent reason, bad flow switch possibly, and boil non moving water in the unit till it burned up).

I was looking at units in the 11K watt range as for me, the flow and temp rise for a given flow (they have charts of this available for most mfgs) was acceptable and I too have enough power to make it work.

HD has an Ariston 4 gal under counter that would fit in the area where my 2.5 gal is now but for $229 I hesitate to spend the money. These small units have a good recovery time.

Charles

Charles... do you leave that water heater turned on all the time? How much do you think it adds to your electric bill?

 

[AV tinker er]

Re: tankkess hotwater heaters

If it draws 57 Amps at 220V, I wonder what it draws at 240V? QUOTE]

Just for future reference Watts = Amps x volts.

So using that formula this unit uses 57 amps x 220 volts = 12540 watts

So if you were to increase the voltage to 240 volts that (12540 watts/240 volts) the amp draw would be reduced to 52.25 amps.

 

[elronin]

Re: tankkess hotwater heaters

This is what I have a Titan water heater on a 60 amp breaker forgot what gauge wire but it's only 2 feet from the breaker box. I got it for 230 dollars and have a backup that's why I set it up with a 3 prong oven type plug so it can be swapped in minutes. It comes with that cable you see from the factory. Have been using it for my whole house for 4 years no problems. Just a heads up I live in south Florida so we don't get very cold down here

 

[Charles (in GA)]

Re: tankkess hotwater heaters

Charles... do you leave that water heater turned on all the time? How much do you think it adds to your electric bill?

I leave it plugged in all winter and probably about the end of May I will unplug it. I am on a community well, so the water is cold out of the ground, but when the ground warms up thoroughly, it will heat the cold water enough (as it passes thru the street main and the long line to my house) to take the bite out of it, and I find I can do without it in the summer. It only takes a few minutes to heat up, so I can turn it on if I need a lot of really hot water.

It is well insulated and I look at the pilot light on it when I pass by and it is almost never on, guess it would be a good candidate for a few weeks with the Kill-A-Watt meter.

Frankly, I think it adds very little to the electric consumption.

If you are considering one of these, get the 4 gal or they have a 6+ gal model but it is too large to go under my sink. When I bought this 2.5 gal Titan I don't think the 4 gal Ariston was on the market.

Charles

 

[justsam]

Re: tankkess hotwater heaters

If it draws 57 Amps at 220V, I wonder what it draws at 240V? QUOTE]

Just for future reference Watts = Amps x volts.

So using that formula this unit uses 57 amps x 220 volts = 12540 watts

So if you were to increase the voltage to 240 volts that (12540 watts/240 volts) the amp draw would be reduced to 52.25 amps.

I guess it depends on what parameter you elect to hold constant. It appears in this case you held power constant, and in my case I held the resistive load constant.

For simplicity, this device is a large heating element, lets ignore the fact that like a light bulb or toaster it has in rush current but once heated steady state current. (I suspect this to be about 40Amps since it is spec'ed as an 8KW element.

For a 57 Amp load at 220V this makes it about a 4 Ohm load. Now hold the load constant, which I believe in this type device is realistic once past in rush current, and apply 240V.
You now have a 60 Amp load. Current went up, and power of course goes up.

A 60 Watt incandescent bulb is a 60Watt bulb at only one voltage level. It can be more or less depending on voltage, in spite of the fact that it says it is a 60 Watt bulb.

 

[scarpozzi]

Re: tankkess hotwater heaters

Gas tankless units are far better than the electric models. (I installed an 8GPM Rhinnai unit 2 months ago and have saved $50+ in electricity so far)

Point of use units are typically efficient, but you may still have a delay in getting hot water...For my gas unit, the delay is about 15 seconds over what my electric tank system was. For about the same money and size, there are small 4 gallon point of use tank systems too that will fit under a sink. I tend to think electric units work better with tank systems. If you go tankless, you may also want to consider throwing a cheap $15 filter on the cold water side to filter out any sediment.

 

[pmiranda]

Re: tankkess hotwater heaters

Home Depot seems to be quoting the wrong specs. The 11KW model draws 57A at 240V (HD shouldn't have put 220... the standard is 240V dammit!). If you only need the 8KW unit, it only draws 40A:
http://www.ecosmartus.com/SiteAssets/file/Spec Flyers/Residential flyer 8-27.pdf

Apparently it is a resistive unit so, like a light bulb, the current draw actually does increase with voltage.

 

[MFolks]

Re: tankkess hotwater heaters

Last week, our hot water supply went out, thinking it might be bad thermocouple, I looked in the furnace room where it's kept, and saw dripping water. The 40 gallon tank had rusted out, killing the standing pilot light.

After calling out plumbing service and spending $1300(with discount), we got a new 40 gallon reem hot water gas fired tank. When the plumber was making out the job report,I asked him about the tankless waterheaters, his advice to me was "unless you have a water softener(we do)expect to suffer problem in six months of less due to hard water"

Our old water heater was as old as our house(25 years), but with the water softner working as it should, we may never have water heater problems again. Just something to think about if want to go with a tankless water heater.....

 

[pmiranda]

Re: tankkess hotwater heaters

We have a big gas-fired Rinnai for our house and modestly hard water (100~150 grains IIRC) and haven't had any issues in a couple years of use. I do flush it annually with vinegar but don't see any scale coming out. So one tip: install flush valves with garden hose thread fittings so you can easily flush it.

 

[CNGsaves]

Re: tankkess hotwater heaters

Last week, our hot water supply went out, thinking it might be bad thermocouple, I looked in the furnace room where it's kept, and saw dripping water. The 40 gallon tank had rusted out, killing the standing pilot light.

After calling out plumbing service and spending $1300(with discount), we got a new 40 gallon reem hot water gas fired tank. When the plumber was making out the job report,I asked him about the tankless waterheaters, his advice to me was "unless you have a water softener(we do)expect to suffer problem in six months of less due to hard water"

Our old water heater was as old as our house(25 years), but with the water softner working as it should, we may never have water heater problems again. Just something to think about if want to go with a tankless water heater.....

Holy blood-suckers Batman . . . . that plumber took you to the cleaners if you paid $1300 for routine replacement of 40 gal natural gas hot water heater!!! That "discount" was more lies and deception . . . wow!!

Cost of heater itself is $300 to $350 (6 yr warranty Bradford White or American Standard) plus say $250, or at most $350 installation, and total comes to $600 to $800 . . . . . thus you were charged almost DOUBLE what it should have been !!!

That "Rheem" name just cost you a killing. I sure hope for that price you have all copper and the very best connections/materials . . . AND . . . and Looooooonnnnnnggg warranty!!

 

[Highbeam]

Re: tankkess hotwater heaters

If it draws 57 Amps at 220V, I wonder what it draws at 240V? QUOTE]

Just for future reference Watts = Amps x volts.

So using that formula this unit uses 57 amps x 220 volts = 12540 watts

So if you were to increase the voltage to 240 volts that (12540 watts/240 volts) the amp draw would be reduced to 52.25 amps.

Ah but AV, you assume wattage is constant when in fact the only thing constant about the element is the resistance. I propose that at higher voltage, the element would consume more watts and so more amps. This will go on until you provide too many amps and the element overheats and burns out.

 

[rburke65]

You folks worrying about 220v vs 240v need to get a life and worry about something relative. My God.....

 

[340fyd]

Thanks for the replies.....I went with the 11kw one..........I'll get it this Thursday......I post up some pictures of install and what ever info whether it's good or bad.