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Products => Crowd Funded Projects => Topic started by: rrpilot on January 02, 2014, 11:53:59 pm

Title: Heatworks Water Heater KickStarter
Post by: rrpilot on January 02, 2014, 11:53:59 pm
Hey, just wondering what you guys think of:

http://www.kickstarter.com/projects/1132758406/heatworks-model-1-your-next-water-heater?ref=discover_rec (http://www.kickstarter.com/projects/1132758406/heatworks-model-1-your-next-water-heater?ref=discover_rec)

I've never owned an inline water heater but I'm very interested in them as I'm always at risk of basement flooding with my water heater tank. Does this technology seem legit?

They are claiming 99% efficiency which seems like bull but I know very little about this stuff.

Anyway, would love to know what others think.
Title: Re: Heatworks Water Heater KickStarter
Post by: mtdoc on January 03, 2014, 12:04:08 am
Quote
Delivers 2.0 GPM of hot water at 240 VAC and 48 amps

And this is special why??

For comparison, this traditional Rheem on demand electric water heater (http://www.rheem.com/product/tankless-electric-water-heaters-tankless-electric-rte-7) can put out 2.5 GPM using 7 kW.

As Dave would say: Fail :--
Title: Re: Heatworks Water Heater KickStarter
Post by: Marco on January 03, 2014, 12:04:57 am
Getting high efficiency in heating is just a question of good insulation.
Title: Re: Heatworks Water Heater KickStarter
Post by: plesa on January 03, 2014, 12:09:03 am
Hey, just wondering what you guys think of:

http://www.kickstarter.com/projects/1132758406/heatworks-model-1-your-next-water-heater?ref=discover_rec (http://www.kickstarter.com/projects/1132758406/heatworks-model-1-your-next-water-heater?ref=discover_rec)

I've never owned an inline water heater but I'm very interested in them as I'm always at risk of basement flooding with my water heater tank. Does this technology seem legit?

They are claiming 99% efficiency which seems like bull but I know very little about this stuff.

Anyway, would love to know what others think.

Do you know exactly hot the heating works?
Title: Re: Heatworks Water Heater KickStarter
Post by: fcb on January 03, 2014, 12:12:29 am
What if you have fairly pure water?

There is something unholy about this concept and besides I can't see it ever getting down to the a sensible price.
Title: Re: Heatworks Water Heater KickStarter
Post by: peter.mitchell on January 03, 2014, 12:43:11 am
Quote
Delivers 2.0 GPM of hot water at 240 VAC and 48 amps

And this is special why??

For comparison, this traditional Rheem on demand electric water heater (http://www.rheem.com/product/tankless-electric-water-heaters-tankless-electric-rte-7) can put out 2.5 GPM using 7 kW.

As Dave would say: Fail :--
[/quote]

The page for that unit is confusing, one page says 2.5gpm, the other says 12.5 :S~!

Also, the unit the kickstarter about seems pointless/redundant.
Title: Re: Heatworks Water Heater KickStarter
Post by: mtdoc on January 03, 2014, 12:48:46 am


The page for that unit is confusing, one page says 2.5gpm, the other says 12.5 :S~!


Yeah, the 12.5 is a typo. HERE (http://www.rheem.com/documents/rte-7-tankless-electric-spec-sheet) is the spec sheet for the whole Rheem tankless electric line of water heaters.

The point is the Kickstarter product claims great efficiency when in reality it is much less efficient than currently available units.
Title: Re: Heatworks Water Heater KickStarter
Post by: Jon86 on January 03, 2014, 12:49:40 am
Quote
Direct electric resistance technology

 :-DD
Title: Re: Heatworks Water Heater KickStarter
Post by: Lurch on January 03, 2014, 01:01:09 am
It shows homes as having several of these fitted, pretty much one for each drawoff point. I doubt there's many places in the world that have domestic supplies capable of supplying enough electricity for 2 of these units to run simultaneously, let alone 3 or 4.

Over here electric showers are popular have been for 30 odd years or more easily. They're still crap, the 7-8.5kW ones are barely usable and the 9kW+ ones are reasonable but not great. That great big 97% efficient gas burning boiler outperforms all of those and is cheaper to run, even taking into account losses in pipework from the boiler to the tap/outlet. The gas burner doesn't need 16mm² cables to every room in the house and a commercial grade 250A supply either.

I'm sticking with gas for the foreseeable future.
Title: Re: Heatworks Water Heater KickStarter
Post by: rrpilot on January 03, 2014, 01:07:32 am
What if you have fairly pure water?

There is something unholy about this concept and besides I can't see it ever getting down to the a sensible price.

Good question ...

It shows homes as having several of these fitted, pretty much one for each drawoff point. I doubt there's many places in the world that have domestic supplies capable of supplying enough electricity for 2 of these units to run simultaneously, let alone 3 or 4.

Over here electric showers are popular have been for 30 odd years or more easily. They're still crap, the 7-8.5kW ones are barely usable and the 9kW+ ones are reasonable but not great. That great big 97% efficient gas burning boiler outperforms all of those and is cheaper to run, even taking into account losses in pipework from the boiler to the tap/outlet. The gas burner doesn't need 16mm² cables to every room in the house and a commercial grade 250A supply either.

I'm sticking with gas for the foreseeable future.

Great point about electricity capacity for the home. Your comment about 7-8.5kW inline heaters is the same thing I normally see when looking at the reviews on these commercial units. I also read a lot about reliability issues which is why this new tech seemed interesting, but as you guys have pointed out, this doesn't exactly have much capacity for the power it requires.

Thanks for all the comments.
Title: Re: Heatworks Water Heater KickStarter
Post by: sleemanj on January 03, 2014, 01:19:36 am
Over here electric showers are popular have been for 30 odd years or more easily.

Electric showers, how bad can that be...
(https://lh6.googleusercontent.com/_pQhZNLDMehw/SZ8f1fdtKII/AAAAAAAAB6I/zrqQ60qy7DA/s800/Kevin%20Mexico%202009%20100-1.jpg)


Image from ADVRider (http://www.advrider.com/forums/showthread.php?t=690767), these types of quality electrical installations are common in South American countries.
Title: Re: Heatworks Water Heater KickStarter
Post by: Frost on January 03, 2014, 01:24:37 am
I doubt there's many places in the world that have domestic supplies capable of supplying enough electricity for 2 of these units to run simultaneously, let alone 3 or 4.

Here in germany these instantaneous water heaters are very common.
I have two of them here installed in the house.
You can install more then two in a single home, but then a "Lastabfallrelais"
(I don't know how it is called in english) is required.

They're still crap, the 7-8.5kW ones are barely usable and the 9kW+ ones are reasonable but not great.
Yes 9kW is crap, all below 20kW is not really usable, the heaters I use have a rated output of 24kW
They work great and are very reliable.

http://www.stiebel-eltron.de/en/privatkunden/warmwasser/produkte/durchlauferhitzer/vollelektronisch-geregelte-durchlauferhitzer/ (http://www.stiebel-eltron.de/en/privatkunden/warmwasser/produkte/durchlauferhitzer/vollelektronisch-geregelte-durchlauferhitzer/)
Title: Re: Heatworks Water Heater KickStarter
Post by: Maxlor on January 03, 2014, 01:31:35 am
They heat the water by running current directly through it using graphite electrodes. Doesn't that cause electrolysis? That'd be very bad given the scale. And doesn't it also corrode the electrodes, even graphite ones (albeit at a slower rate than, say, steel ones,) which would mean that they'd need to be replaced after a while?
Title: Re: Heatworks Water Heater KickStarter
Post by: Lurch on January 03, 2014, 01:34:34 am
Here in germany these instantaneous water heaters are very common.
I have two of them here installed in the house.
You can install more then two in a single home, but then a "Lastabfallrelais"
(I don't know how it is called in english) is required.

Would appear to be a relay/contactor, similar to what we have in the UK for the off-peak/economy 7 circuits. I think the gist is that it only allows you to use the second heater if nothing else is in use, or vice-versa, so a bit of a compromise in that you're knackered if you want to turn on a hot tap at the wrong time of day while someone else is. Not sure if you could cascade them but still not an ideal solution even if you could.
Title: Re: Heatworks Water Heater KickStarter
Post by: Rufus on January 03, 2014, 01:50:05 am
I also read a lot about reliability issues which is why this new tech seemed interesting, but as you guys have pointed out, this doesn't exactly have much capacity for the power it requires.

Unless it heats up the air around it it will have exactly the capacity of the power it draws. There are no losses turning electricity into heat - just the possibility of some of that heat not going into the water where you want it.

The kickstarter page and their web site is full of shit. They talk about graphite heating elements which never get hotter than the surrounding water. You would think someone making water heaters would understand the 2nd law of thermodynamics - but apparently not. Water containing capacity - 1.5 cups - just lol.

Maybe graphite heating elements are more reliable than more conventional ones but all you have is their claim that they are and they are full of shit.

If I were in the business of installing such heaters I might be interested in evaluating them. If I wanted to install a water heater in my house I wouldn't risk buying one of these. A kickstater campaign seems a bit ridiculous or desperate. If they really have a product that works better than existing technology, is reliable, and has reasonable cost they would have no problem demonstrating that and selling them.
Title: Re: Heatworks Water Heater KickStarter
Post by: Frost on January 03, 2014, 01:51:20 am
I think the gist is that it only allows you to use the second heater if nothing else is in use, or vice-versa

Thats right, I can use two of them at the same time but not more than two.
So if more then two heaters are installed on one network,
it must be ensured that only two can operate at the same time.
Title: Re: Heatworks Water Heater KickStarter
Post by: Psi on January 03, 2014, 02:33:37 am
What if you have fairly pure water?

I was wondering that too.
It probably wouldn't work in some parts of NZ where the tap water comes down from the mountains and is so pure it doesn't need chlorination.

Switzerland as really pure tap water as well.


Note: There's a difference between safe tape water (lots of water treatment) and pure water (no treatment needed)
Title: Re: Heatworks Water Heater KickStarter
Post by: gxti on January 03, 2014, 06:38:11 am
They heat the water by running current directly through it using graphite electrodes. Doesn't that cause electrolysis? That'd be very bad given the scale. And doesn't it also corrode the electrodes, even graphite ones (albeit at a slower rate than, say, steel ones,) which would mean that they'd need to be replaced after a while?
Actually tank-based water heaters, even the gas ones, have a sacrificial anode. I have no idea what it's for but it needs replacement after many years. It does seem like anodes used in direct electric heat would wear out very quickly but I don't know anything about the technology.
Title: Re: Heatworks Water Heater KickStarter
Post by: SeanB on January 03, 2014, 07:18:56 am
Sacrificial anode is there to protect the metal parts of the tank from corrosion. The anode corrodes preferentially and protects the brass, copper and steel parts until it is gone. Made from a magnesium/zinc alloy it will last around 5 years on a soft water supply, up to 15 in a hard water area. The current generation of tanks have a steel shell with a glass coating on them for protection. No more copper tank ( at the scrap price of copper no wonder) and very little brass fittings used on them. I replaced a valve on one 2 months ago, and stripped the tank and cleaned it while doing the draining. Inside there was a thick layer of sludge from the incoming water, leaving a 3cm layer at the bottom of the tank that drained off looking like tea. That was the settlings from what got past the 100 micron inlet filter on that line set. Glass lining and anode were fine, not surprising as it is only 2 years old. Replaced the filter cartridge as well, with a 5 micron unit. Old one looked like a brown blob from what was in the supply line.

As to heater efficiency the best improvement is to add insulation to the piping to and from the tank for the first meter, that will drop your standing loss by at least 50%, and adding extra insulation to the tank ( I used a roll of wall insulation wadding, light green fibre made from recycled PET bottles) drops it a further 30%. Made a big difference in the electricity bill.
Title: Re: Heatworks Water Heater KickStarter
Post by: Alphatronique on January 03, 2014, 05:12:34 pm
https://www.google.com/patents/US7817906? (https://www.google.com/patents/US7817906?)

from it patents

The predominant alternative to using heating elements to heat the liquid is to pass an electrical current through the liquid by passing it between two electrodes between which a voltage exists. The voltage is preferably an AC voltage so as to avoid electrolysis of the liquid. This method is known as direct electrical resistance (DER) heating. Probably the most common application of this approach (although relatively crude) is in vaporizers used to humidify room environments. One reason for the popularity of the approach is that it is intrinsically safe: no electrical current can flow if there is no liquid between the electrodes.

"The predominant alternative"    so if it predominant way ,it not novel so wly issue a patent on this ?
ok some one at patent office have already put patent on PWM on a led so wly not after all ... :-DD

an personally i have doubt on claim efficient and  safety   ,if water was pure it become a good insulator > 5MEG / Cm
and if water was hard and use plastic plumbing it may expose  user to main supply. :scared:

and if electric fault turn one of power driver into a diode you got really powerful explosive gas generator  :-DD

Title: Re: Heatworks Water Heater KickStarter
Post by: fcb on January 03, 2014, 06:25:44 pm
Hmm.. Let's be generous and use the spec's they quote on their KS.

1.5KW @ 100VRMS = 6.66 ohms
13.3KW @ 277VRMS = 5.77 ohms

I've just measured my tapwater resistance across two stainless metal rulers approx. 20mm apart, I get something like 6Kohms (it keeps climbing).

We are in an area of the UK which gets "very hard" water, and we don't use a water softener (we get through at least one electric kettle per year, and fit a new washing machine element every 3-4 years I guess), so I would expect our water to be lower impedance than the UK average.

Even if the KS units elements are closer, and much bigger, I cannot imagine how they hit even their lowest 'capacity' rating.  What am I missing here?
Title: Re: Heatworks Water Heater KickStarter
Post by: Alphatronique on January 03, 2014, 07:29:16 pm
it may use lot of very close spaced plate for increase surface area
and or switching  power supply for increase voltage

but since water hardness vary allot i hard to handle  ,here it spring water whit  < 100 ppm

and very close placed plate may short whit sediment deposit ,and high power electronic whit DC-DC was likely to fail

i prefer simple and inexpensive electric heater  O0
Title: Re: Heatworks Water Heater KickStarter
Post by: fcb on January 03, 2014, 09:08:37 pm
The picture on the KS (kickstarter) shows a number of plates, perhaps 4 or 5 I could see.

They *could* use a SMPSU to boost the voltage and then alternate this across the plates - BUT it wouldn't be 99% efficient as they claim - I don't think they do.

It certainly doesn't look like 'vapourware' from the photos so I guess they must have proximity & surface area.

One other thing? How are they preventing leakage to earth from any current flowing out from the unit to metal piping at either end.  If one electrode was at 100VRMS and the impedance of the water from the end of the electrode through the outlet to metal pipe was, say, 10K - they would have 10mA earth current - perhaps 20mA if it's the same design at the inlet.  Surely enough to get ELCB's twitching?
Title: Re: Heatworks Water Heater KickStarter
Post by: Lurch on January 03, 2014, 09:18:05 pm
One other thing? How are they preventing leakage to earth from any current flowing out from the unit to metal piping at either end.  If one electrode was at 100VRMS and the impedance of the water from the end of the electrode through the outlet to metal pipe was, say, 10K - they would have 10mA earth current - perhaps 20mA if it's the same design at the inlet.  Surely enough to get ELCB's twitching?

Maybe the continuous output adjustment somehow means that the plates aren't live for a full cycle? The blurb appears to infer that it is adjusted 50/60 times per second.
Title: Re: Heatworks Water Heater KickStarter
Post by: fcb on January 03, 2014, 10:47:44 pm
One other thing? How are they preventing leakage to earth from any current flowing out from the unit to metal piping at either end.  If one electrode was at 100VRMS and the impedance of the water from the end of the electrode through the outlet to metal pipe was, say, 10K - they would have 10mA earth current - perhaps 20mA if it's the same design at the inlet.  Surely enough to get ELCB's twitching?

Maybe the continuous output adjustment somehow means that the plates aren't live for a full cycle? The blurb appears to infer that it is adjusted 50/60 times per second.
I don't think they will make any difference.  If they are pumping X kilowatts into the water they could well get X mA to earth.

I've briefly (very) looked at the patent linked in a previous comment, it certainly looks like it would/should work. However the unit they show on the KS page doesn't look like it has the 'plurality' of channels..

Perhaps it will succeed on KS, but can't help but think it's going to be a commercial flop.
Title: Re: Heatworks Water Heater KickStarter
Post by: Lurch on January 03, 2014, 10:51:17 pm
I don't think they will make any difference.  If they are pumping X kilowatts into the water they could well get X mA to earth.

No, clutching at straws here tbh.

Perhaps it will succeed on KS, but can't help but think it's going to be a commercial flop.

I've seen loads of electric space and water heating products touted as clean/efficient/simple/instantaneous etc... over the last 20 years of being in the trade. Still don't find them being fitted unless there is no other option.
Title: Re: Heatworks Water Heater KickStarter
Post by: peter.mitchell on January 04, 2014, 12:35:48 am
IMHO, it doesnt matter if its 70-80-99% efficient, you're still heating water with electricity you are buying from the grid, its gonna be expensive.
Title: Re: Heatworks Water Heater KickStarter
Post by: fcb on January 04, 2014, 01:34:29 am
IMHO, it doesnt matter if its 70-80-99% efficient, you're still heating water with electricity you are buying from the grid, its gonna be expensive.

Yes, it does.

Let's say the unit has SMPSU inside and it runs at 1W (perhaps doing housekeeping, checking for water demand, servicing the Wifi(!), lighting a pretty blue LED, etc...). Also, lets assume that the unit is in your downstairs toilet and gets used for 1 minute a day at 5KW.

SMPSU daily draw: 24Whrs/day
Water heater draw: 83Whrs/day
Efficiency: 77.6%

I accept that the case is different if you put it in a shower, the warm-up time of an electric shower is a couple of seconds and even if the 'direct' heater unit is quicker - it's not going to be instant - which means I still get hit with a blast of cold water unless if hold the shower head out of the way momentarily.

Now if they incorporated their technology directly into the shower head... that would be sexy.
Title: Re: Heatworks Water Heater KickStarter
Post by: peter.mitchell on January 04, 2014, 03:21:53 am
IMHO, it doesnt matter if its 70-80-99% efficient, you're still heating water with electricity you are buying from the grid, its gonna be expensive.

Yes, it does.

Let's say the unit has SMPSU inside and it runs at 1W (perhaps doing housekeeping, checking for water demand, servicing the Wifi(!), lighting a pretty blue LED, etc...). Also, lets assume that the unit is in your downstairs toilet and gets used for 1 minute a day at 5KW.

SMPSU daily draw: 24Whrs/day
Water heater draw: 83Whrs/day
Efficiency: 77.6%

I accept that the case is different if you put it in a shower, the warm-up time of an electric shower is a couple of seconds and even if the 'direct' heater unit is quicker - it's not going to be instant - which means I still get hit with a blast of cold water unless if hold the shower head out of the way momentarily.

Now if they incorporated their technology directly into the shower head... that would be sexy.

But hey, lets use that same crazy low figure you showed there, bam, that figure is crazy low, even though the efficiency is low, it is still quite low over all, so you can power it from a non grid energy source for "free"
Title: Re: Heatworks Water Heater KickStarter
Post by: Stonent on January 04, 2014, 06:41:49 am
http://www.noritz.com/ (http://www.noritz.com/)

That's one I hear about frequently.
Title: Re: Heatworks Water Heater KickStarter
Post by: fcb on January 04, 2014, 01:40:32 pm
I love the picture on their w/s of the installation in the garage... is that a... Prius
Title: Re: Heatworks Water Heater KickStarter
Post by: Lurch on January 04, 2014, 04:20:21 pm
I was watching This Old House the other day from 2003. Kevin thingy was was getting a hard on over a front loading washer and dryer because of how modern and easy to use they are. We've been using them for 30 odd years+ They were also extolling the virtues of this new fangled gas burning water heater. We've been using gas to heat water for 40-50 years or more.

http://www.noritz.com/ (http://www.noritz.com/)

That's one I hear about frequently.

We stopped using single point gas water heaters in the 70's.
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 10, 2014, 05:58:21 pm
People,
As the inventor , please allow me to clarify a few things.
I understand the skepticism when approaching an entirely new technology, especially one that is clearly disruptive and replaces what has commonly been used for decades.  Your point is that our claim of using graphite heating elements, cannot be true.  We do not use graphite heating elements. We do not use heating elements at all.  We do not employ any aspect of heat transfer.  Our technology (and our patent) is based on Direct Energy Resistance. This technology heats the water by passing a current though one or more pairs of graphite electrodes (which are not heating elements, but electrical conductors, which is why they do not get hotter than the water) , which excite the water molecules causing friction between the molecules, which results in the water heating itself.  Same concept as a microwave, except we use a different method to excite the water molecules. Same method as NUCOR and other steel mills use to melt steel; pass enough current through the material (in this case water) and it gets hotter. So the is no latent heat - zero.  Its like comparing a water proof toaster to a microwave. 2nd law of thermo does not apply here.
Since the electrodes don't get hot like heating elements, they do not get mineral deposition, or "scale" on them.
Rheem constantly makes misleading headline statements about they capacity. For example, they claim 4 GPM at 13kW. When you read the fine print, that results in a 20 degree temp rise, which unless you have incoming water at 90 degrees, is not going to give you a warm shower. The equation for all tankless is kW X 6.83 = temp rise (F) X GPM. You can see that their, and other units, follow this formulas as do we. You cannot beat physics.
I suspect some of you are thinking that this is a dangerous device; 1) Current only passes through one or more pairs of electrodes, creating a circuit, with no stray currents. However, we have added two grounding plates in the water chambers as a safeguard and we have passed UL 499 standard in our lab, which assures safety. Any and all units we ship will pass the $(( standard as certified by an outside lab, such as UL or TUV.
If you want to see the US patent, it is number 7,817,906
There are many reasons why people post projects on Kickstarter. Maybe some are desperate, we are not.
Thanks
Jerry Callahan
Title: Heatworks Water Heater KickStarter
Post by: madshaman on January 10, 2014, 06:14:34 pm
My two cents: power purchased from the grid is probably the most expensive way to heat water. There are plenty natural-gas based inline products and burning gas to create heat is as close to efficient as you can get.

I'm also not keen on the idea of a high potential being applied to the liquid I'm filling my bathtub with (didn't read the site, basing this on the "direct electrical resistance technology" quote shared).  I'm sure it's all failsafe and that but..
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 10, 2014, 06:24:57 pm
No doubt gas is less expensive than electricity, but half of US does not have gas.
As far as safety, electricity always take the path of least resistance, which is not going to be from the water heater to you, it would be from inside the water hear to the ground plates inside the water heater. And, safety is why UL is in business, which is why we value and comply with their testing standards.
Thanks,
Jerry
Title: Heatworks Water Heater KickStarter
Post by: madshaman on January 10, 2014, 06:46:32 pm

No doubt gas is less expensive than electricity, but half of US does not have gas.
As far as safety, electricity always take the path of least resistance

Thank-you for your reply.  I must disagree with your statement about the path electricity takes.  It is my belief that current flows through all possible paths, the amount of current (at low frequencies) being determinable by applying Ohm's law and using Kirchhoff's laws.

I agree the because charge carriers are quantum phenomena that there are paths where the current truly is zero over small local intervals of time.

That being said, it is still conceivable that a return path through someone's body exists that has low enough impedance relative to the most conductive return path and significant current *will* flow through that body.

Although unlikely, municipal water isn't perfectly homogeneous and unforeseen mineral deposits and/or chemical reactions within the water system really can create a scenario where measurable current could flow through an unintended load; such as a baby.

I'm sure your system is safe, but to make a statement like "electricity always takes the path of least resistance" is grossly inaccurate (as it implies: electricity *only* flows along the path of least resistance); no-one's electronics would work at all if this were true, and this statement doesn't really indicate any real measure of safety.
Title: Re: Heatworks Water Heater KickStarter
Post by: remixed123 on January 10, 2014, 06:47:30 pm
Hey Jerry, really interesting technology, it could as you suggest change the way we heat our water. No need for dual pipes and all the waste that happens with the current solution. It also looks like a space saver, which is becoming more important with high density apartments.

I kind of laughed when I thought about the change or should I say return to the past. One of the first places I rented when in 2nd year at uni in the 80s had individual gas water heating for the bathroom and kitchen. It was dangerous and not very effective, not the best device for drunk uni students!

Best of luck with the kickstarter, looks like you have already hit your target, so it's off to a good start.

Glenn.
Title: Re: Heatworks Water Heater KickStarter
Post by: Rufus on January 10, 2014, 07:17:51 pm
We do not use graphite heating elements. We do not use heating elements at all.

Then maybe your kickstarter campaign shouldn't say this

Quote
HEATWORKS MODEL 1's graphite heating elements never get hotter than the surrounding water

and this being an electronic engineering forum we know how resistors work.
Title: Re: Heatworks Water Heater KickStarter
Post by: Rufus on January 10, 2014, 07:37:48 pm
Another thing. I wondered how it managed to do without a flow sensor or switch which they criticise existing units for having.

The patent reveals they don't manage. The 1 1/2 cups (lol) of water in the unit are kept at the set delivery temperature 24/7 which will cripple the efficiency of installations where hot water is infrequently required.
Title: Re: Heatworks Water Heater KickStarter
Post by: SeanB on January 10, 2014, 07:49:07 pm
So not an instant heater rather a very small storage cylinder with a really overrated element. Wonder how well the insulation performs. Here the standard is pretty lax, 2.3kWh per 24 hour period. that means you use typically 2.3 units per day to just keep the water hot. I improved that by more insulation and by insulating the water lines into and out of the unit.
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 10, 2014, 11:59:07 pm
So let me answer a few things.
1) We corrected the language on the KS page to better reflect the technology. The language about heating elements was wrong  and it got past me. Sorry about that.
2) All "tankless" water heaters have about that same amount of water in them, but to do without the flow switch is of paramount importance. The amount of energy to keep that small amount of water warm is insignificant.
3) So when existing tank or tankless units's heating elements fail, what happens? The current goes into the water until the breaker trips. Ours is designed to do the same thing, and we add two ground plates as well.
Thanks for the input.
Title: Re: Heatworks Water Heater KickStarter
Post by: tszaboo on January 11, 2014, 05:04:28 am
Ok. I have this: http://en.wikipedia.org/wiki/Hard_water (http://en.wikipedia.org/wiki/Hard_water) If I have a boiler, that would still work. With your "direct heating resistance whatever" we have a very good electrical isolator on the electrodes, so after time, the output power declines, until unusable. Than, since cleaning a graphite is impossible, I have to replace my electrode. Every 6-12 months, looking at the kitchen sink.
Title: Re: Heatworks Water Heater KickStarter
Post by: Lurch on January 11, 2014, 01:43:37 pm
Ok. I have this: http://en.wikipedia.org/wiki/Hard_water (http://en.wikipedia.org/wiki/Hard_water) If I have a boiler, that would still work. With your "direct heating resistance whatever" we have a very good electrical isolator on the electrodes, so after time, the output power declines, until unusable. Than, since cleaning a graphite is impossible, I have to replace my electrode. Every 6-12 months, looking at the kitchen sink.

You need a water softener.
Title: Re: Heatworks Water Heater KickStarter
Post by: tszaboo on January 11, 2014, 06:02:52 pm
Ok. I have this: http://en.wikipedia.org/wiki/Hard_water (http://en.wikipedia.org/wiki/Hard_water) If I have a boiler, that would still work. With your "direct heating resistance whatever" we have a very good electrical isolator on the electrodes, so after time, the output power declines, until unusable. Than, since cleaning a graphite is impossible, I have to replace my electrode. Every 6-12 months, looking at the kitchen sink.

You need a water softener.
OK, I will just tell it to the landlord. He will probably jump with joy to install one for me.
Title: Re: Heatworks Water Heater KickStarter
Post by: fcb on January 14, 2014, 05:39:45 pm
Hmm.. Let's be generous and use the spec's they quote on their KS.

1.5KW @ 100VRMS = 6.66 ohms
13.3KW @ 277VRMS = 5.77 ohms

I've just measured my tapwater resistance across two stainless metal rulers approx. 20mm apart, I get something like 6Kohms (it keeps climbing).

We are in an area of the UK which gets "very hard" water, and we don't use a water softener (we get through at least one electric kettle per year, and fit a new washing machine element every 3-4 years I guess), so I would expect our water to be lower impedance than the UK average.

Even if the KS units elements are closer, and much bigger, I cannot imagine how they hit even their lowest 'capacity' rating.  What am I missing here?

So ISI, from the picture on the KS I see 4 graphite electrodes, assuming that two these are 'grounding plates' can you answer the following questions:
1. How big are the electrodes (H x W)?
2. How far apart are the electrodes?

I have some supplementary questions too, but I understand if you haven't tested for them or it's proprietary knowledge:
3. How much current flows through earth on a typical unit?
4. How do you prevent limescale building up on the electrodes?
5. How do you measure water-flow and/or temperature?
6. Will the unit work with purified water?

Title: Re: Heatworks Water Heater KickStarter
Post by: Rufus on January 14, 2014, 05:49:13 pm
I have some supplementary questions too,

The patent mentioned above answers most of your questions.
Title: Re: Heatworks Water Heater KickStarter
Post by: Galaxyrise on January 14, 2014, 06:04:26 pm
OK, I will just tell it to the landlord. He will probably jump with joy to install one for me.
How is it that you're in a position to install an in-line water heater but not a water softener?
Title: Re: Heatworks Water Heater KickStarter
Post by: fcb on January 14, 2014, 06:51:10 pm
I have some supplementary questions too,

The patent mentioned above answers most of your questions.

I've read the patent, and I'm fine with that. EXCEPT the picture on the KS website shows a fairly large plain/flat graphite colored electrode AND the pic of the assembly shows what looks like four electrodes (ISI state that there are a pair of earthing electrodes).

Now the patent referenced shows multiple electrodes arranged in channels with small gaps between them, this I fully expect would work, however I cannot see how the water between the two large plain/flat electrodes placed a distance apart (again looking at the picture) can hit 5-6 ohms.

I'm sure the KS is genuine and that the technology works, just wondering what I am missing????
Title: Re: Heatworks Water Heater KickStarter
Post by: tszaboo on January 15, 2014, 06:19:02 pm
OK, I will just tell it to the landlord. He will probably jump with joy to install one for me.
How is it that you're in a position to install an in-line water heater but not a water softener?
I'm just trolling here. No actually I would never buy one of these, as gas is the only viable solution for water heating, after the sun of course.
But you see, that this new construction has some unresolved issues, I pointed out.
Title: Heatworks Water Heater KickStarter
Post by: madshaman on January 16, 2014, 06:25:04 pm

OK, I will just tell it to the landlord. He will probably jump with joy to install one for me.
How is it that you're in a position to install an in-line water heater but not a water softener?
I'm just trolling here. No actually I would never buy one of these, as gas is the only viable solution for water heating, after the sun of course.

Omg, thank-you for freaking saying it; for an engineering forum, this should be obvious.
Title: Re: Heatworks Water Heater KickStarter
Post by: Rufus on January 16, 2014, 06:47:42 pm
I'm just trolling here. No actually I would never buy one of these, as gas is the only viable solution for water heating, after the sun of course.

Omg, thank-you for freaking saying it; for an engineering forum, this should be obvious.

It isn't obvious or true. Gas isn't available everywhere. Where I am gas is about 1/3rd the price of electricity by energy content. Heating water with gas is less efficient than with electricity. The equipment and installation are much more expensive for gas. For a local supply of hot water you need a local flue which may not be possible, otherwise you heat a lot of water in pipes which gets wasted.

Electricity may be the only option and where it isn't it is still viable depending on where and hot much hot water you want.
Title: Re: Heatworks Water Heater KickStarter
Post by: Poe on January 17, 2014, 09:27:42 pm
That quote....

People,
As the inventor , please allow me to clarify a few things.
I understand the skepticism when approaching an entirely new technology, especially one that is clearly disruptive and replaces what has commonly been used for decades.  Your point is that our claim of using graphite heating elements, cannot be true.  We do not use graphite heating elements. We do not use heating elements at all.  We do not employ any aspect of heat transfer.  Our technology (and our patent) is based on Direct Energy Resistance. This technology heats the water by passing a current though one or more pairs of graphite electrodes (which are not heating elements, but electrical conductors, which is why they do not get hotter than the water) , which excite the water molecules causing friction between the molecules, which results in the water heating itself.  Same concept as a microwave, except we use a different method to excite the water molecules. Same method as NUCOR and other steel mills use to melt steel; pass enough current through the material (in this case water) and it gets hotter. So the is no latent heat - zero.  Its like comparing a water proof toaster to a microwave. 2nd law of thermo does not apply here.
Since the electrodes don't get hot like heating elements, they do not get mineral deposition, or "scale" on them.
Rheem constantly makes misleading headline statements about they capacity. For example, they claim 4 GPM at 13kW. When you read the fine print, that results in a 20 degree temp rise, which unless you have incoming water at 90 degrees, is not going to give you a warm shower. The equation for all tankless is kW X 6.83 = temp rise (F) X GPM. You can see that their, and other units, follow this formulas as do we. You cannot beat physics.
I suspect some of you are thinking that this is a dangerous device; 1) Current only passes through one or more pairs of electrodes, creating a circuit, with no stray currents. However, we have added two grounding plates in the water chambers as a safeguard and we have passed UL 499 standard in our lab, which assures safety. Any and all units we ship will pass the $(( standard as certified by an outside lab, such as UL or TUV.
If you want to see the US patent, it is number 7,817,906
There are many reasons why people post projects on Kickstarter. Maybe some are desperate, we are not.
Thanks
Jerry Callahan

This might be an improvement over inline electric tankless water heaters, but lets be honest.  Electric tankless systems are a novelty, up-sold by contractors to the impatient wealthy.  They are not a replacement for the traditional tank system and MUST be used in conjunction. 

Your marketing is pretty devious.  It makes all kinds of implications, insinuations and just incorrect statements concerning your system in comparison to other heating systems.  Most of the time you're really spinning the numbers and making crazy assumptions behind the scenes. 

Nearly half of all residential water heaters in the USA are conventional electric tank systems.  Less than 1% (using any metric other than total installation cost per GPM) are electric tankless systems because they just suck in every way. 

Lets limit comparisons to other electric systems. There are really only two.  The cheap (traditional tanks) and the best (heat pumps).

First, efficiency....
Even the cheap conventional water heaters are >90% efficient!  Go online, find a cheap water heater, look at the mfr specs and how they measure efficiency.

Quote from: ISI KS page
"The largest drawback of tank water heaters is that they waste a tremendous amount of energy heating water when no one is using hot water."
nope.

THAT 90% EFFICIENCY NUMBER INCLUDES ANY HEAT LOST WHILE SITTING THERE OVER 24HOURS!
eCFR Code of Federal Regulations...
10 CFR 430, Subpart B, Appendix E..
"Uniform Test Method for Measuring the Energy Consumption of Water Heaters"
5.1.5.24
"24-Hour Simulated Use Test"


Conventional electric storage water heaters have improved REAL WORLD efficiency results thanks to this extended testing period.  It forced manufacturers to add internal liners, outer coatings, better R-value bulk insulation, eliminate drafty outer shells, isolated the base, use two heating elements and put thermal taps on the ports. 

Heat pumps produce just as much hot water, but consume a half (real world typical) as much power.  No violation of thermo.

How does Heatwork's tankless 99% efficient unit provide "up to 40% energy savings" unless it's compared to...something else?  All cost saving comparisons I find on the KS page were referencing gas heater numbers or in the case of that EnergyStar pamphlet, specs from systems that haven't existed for half a century....

Operational cost savings...
Cost comparison with a traditional tank is easy (90% vs 99%).  A typical family would therefore see an average annual savings less than $50

ROI = 'div by zero'

Comparing to the operational cost of a heatpump is also easy.  The Heatworks unit consumes, on average, twice as much power.
 
Space and Installation costs...

Tankless systems either take up your storage areas or they require holes punched in your walls, pipes and two phase lines run to those walls and access panels installed. 
"you will save space with our small 12" long unit rather than a big 46" unit!"
With plumbing, junction boxes capable of handling 10AWG wire and access panels, how much space does this 12" thing take up?  How many of these small 12" units will I need to install to replace one $300 conventional tank?  I might need more rooms in my house.

You say in your video that:
"in new construction, it's actually less expensive, up-front, to install these around the house, ... and run cold water and electrical wiring to them, than it is to run hot water pipe through the house."

I'm waiting for the disclaimer on this one.  Considering your product's capacity is so low that it needs to be used in conjunction with a conventional hot water tank.....a tank that gets water to your product with hot water lines....

Capacity...
I have two 7GPM showers and four 2GPM sinks.  My water comes from the utility at 55F and I want it 120F.  So each of my showers would need 66KW (7 of these units), and my sinks would each need 19KW (two units).  My entire home service is only rated at 44KW and I need to supply 210KW!?  Assuming I dedicate an entirely new electrical service to these things, and only let one turn on at a time... I can just barely take a comfortable shower?

Water savings......
The "10% water savings" statement assumes that 10% of my TOTAL water consumption is allowed to flow down the drain, right?  A large amount of the water I use is 100% cold water.  Dishwaster, cooking, drinking, toilets.  These things don't let the water run while waiting for the warm stuff.  To offset this fact, I would need to increase the relative percentage of time I waste water while waiting.  So how do you calculate the average amount of hot water that goes down the drain?! 

In your video you say that this unit saves one to two GPM every time you use your hot water tap.  What does that even mean?  It restricts my flow by 1.5GPM?  Couldn't I do the same with an obstruction like a hunk of dirt?  Then you state it saves 20 to 40 gallons per day without explaining how that is even possible.

The alternatives...
Heat pumps are better solution to any hot water system in every way.  They consume (typically) half the power as even this 99% efficient system for the same heat output as a conventional tank (no violation of thermo laws).  They are able to service an entire REAL WORLD home, not a home that only turns on one super low flow faucet on at a time.  Upfront costs of heat pumps are the only down side.  Although more expensive than conventional $300 tanks, they have a measurable ROI over something like this. 

This device might have applications, but I don't see them.  Anyone that wants the luxury of instant hot water just needs to install a circulating bleed valve.  It's a very cheap DIY project that bleeds a very small amount of hot water from the far end of the house to mix with the cold supply periodically.  This keeps the hot water supply line warm without wasting much energy.  Simple and cheap.





Title: Re: Heatworks Water Heater KickStarter
Post by: mtdoc on January 17, 2014, 10:05:07 pm

Heat pumps are better solution to any hot water system in every way.  They consume (typically) half the power as even this 99% efficient system for the same heat output as a conventional tank (no violation of thermo laws).  They are able to service an entire REAL WORLD home, not a home that only turns on one super low flow faucet on at a time.  Upfront costs of heat pumps are the only down side.  Although more expensive than conventional $300 tanks, they have a measurable ROI over something like this. 

This device might have applications, but I don't see them.

Absolutely spot on.  :-+

I have a Nyle Geyser (http://water.nyle.com/residential/) heat pump unit that works great.  It plugs into a 120V outlet and with the 240V service to our 50 gallon standard electric tank turned off, in the summer, with the tank cold,  it will take our water from 50 F to 120 F drawing about 600 watts over 4 hours.  Exact power use depends on the ambient temperature of the surrounding air in our basement untility room- with colder temps it uses more power. In the summer it allows us to heat our hot water with excess PV power from our solar system. As a bonus it cools and dehumidifies the utility room which also serves as my lab! ;D

The nice thing about these units is that they are separate from the tank - so that when the tank dies - you just hook it up to the new one. The popular GE Geospring units are part of the tank themselves and must also be replaced.

Tankless, on demand propane units do make sense in some situations and sometimes so do tankless electric - but this "Heatworks" kickstarter unit makes no sense to me - I see no advantages to what is already available and plenty of disadvantages. :--

Title: Re: Heatworks Water Heater KickStarter
Post by: sync on January 17, 2014, 10:06:24 pm
In Germany the tankless water heaters uses not insulated heating wire which is in direct contact with water. Low thermal mass and low losses. Age-old technology which simply works. They last decades without maintenance. I don't see an advantage of this new technology.
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 23, 2014, 10:58:53 pm
To FCB.
The photo on the KS campaign was meant to  show what the electrodes look like, not the whole array, which would be hard to distinguish in a photo (we tried!) and these are not the earthing electrodes.
Thanks for your thoughts,
Jerry
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 23, 2014, 11:02:30 pm
To sync,
The biggest advantage is that our technology does not get scaling or mineral deposits which cause all electric tank heating elements to overheat and fail. Most Europeans know that they should have their units descaled, sometimes as frequently as once a year.
Thanks,
Jerry
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 23, 2014, 11:07:41 pm
To Poe,
I find it hard to reply to someone who clearly has not read or understood the material and is suspicious of everything we state without the benefit of basic knowledge, so I won't.
If you (or anyone) want to learn more, please email me at info@isitechnology.com
Thanks,
Jerry
Title: Re: Heatworks Water Heater KickStarter
Post by: sync on January 24, 2014, 02:00:35 pm
To sync,
The biggest advantage is that our technology does not get scaling or mineral deposits which cause all electric tank heating elements to overheat and fail. Most Europeans know that they should have their units descaled, sometimes as frequently as once a year.
Thanks,
Jerry
That's not a problem with the tankless heaters I mean. They are self cleaning due the thermal expansion and contraction of the heating wire. They run decades without maintenance.
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 24, 2014, 02:30:12 pm
To Sync,
That is not actually true for tankless electric. This is from Stiebel Eltron's web site.
Thanks,
Jerry
Does my Stiebel Eltron tankless electric water heater need to
be vented?

» Stiebel Eltron tankless electric water heaters are designed for a very long service life, but actual life expectancy will be directly affected by water quality and use. If you do not already know the quality of your water, we advise testing (your water department may be able to assist). Installing a non-salt based softener or polyphosphate inline filter may prolong the life of your unit. Stiebel Eltron recommends the HousePure® water filter (our Part No. 581331) for this purpose. To ensure consistent water flow, we recommend periodically checking for and removing any scale and dirt in the faucet aerators and showerheads, and in the filter screen in the unit. Depending on water hardness, scale build-up may need to be flushed from the unit every six months to a year. This will prolong the life of your water heater, and help ensure optimal performance. We recommend our Flow-aide Descaling Kit (our Part No. 540000) for this purpose. Alternatively white vinegar or CLR® Calcium, Lime & Rust Remover may be used.

Descaling procedure, step-by-step:

1. Disconnect power to water heater.
2. Close hot and cold isolation and service valves and remove service caps.
3. Pour 1.5 gallons of water into bucket and place under water heater.
4. Add contents of 1 quart bottle of Flow-aide into bucket (bucket should be filled approximately ½ full).
5. Connect one hose pump, and other end of same hose to cold service valve. Place pump in bucket.
6. Connect second hose to hot service valve. Place other end in bucket.
7. Open both hot and cold service valves.
8. Plug pump into grounded receptacle.
9. Allow pump to circulate Flow-aide solution through heater for 30-45 minutes. Unplug pump.
10. Close cold service valve. Remove hose from cold service valve, and replace service cap.
11. Disconnect the hose from the pump and remove pump from bucket. Discard Flow-aide solution.
12. Flush tankless water heater for 3-5 minutes or until water flows clear by opening the cold isolation valve and allowing water to exit through the hot service valve into a drain or bucket. If using a bucket, empty periodically.
13. Close hot service valve. Remove hose from service valve and replace service cap.
14. Open hot isolation valve.
15. Connect power to water heater and return appliance to service.
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 24, 2014, 02:40:16 pm
Sorry,
when i cut and pasted I copied this by mistake. Please ignore in previous post.
Thanks,
Jerry

Does my Stiebel Eltron tankless electric water heater need to
be vented?
Title: Re: Heatworks Water Heater KickStarter
Post by: sync on January 24, 2014, 04:37:16 pm
I found this picture on www.stiebel-eltron-usa.com (http://www.stiebel-eltron-usa.com). This is not the kind of heating element what I mean. These have a cooper tube around the heating wire. And they need to be descaled.
(http://www.stiebel-eltron-usa.com/images/dhc_coil.jpg)

What I mean are heaters which have the bare heating wire in direct contact with the water. No extra tube around them.
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 24, 2014, 06:57:46 pm
Sync,
Inside those coils are the wire resistance heating elements. SE uses the outer pipe to slow down the degradation of those wire coils, but obviously they still need to be descaled.
This is from the Bosch web site, and Bosch uses bare wires. The reality for large or small resistance heating elements is that they get scale, and thermal expansion and contraction of the wire does not keep them from scaling.
Thanks,
Jerry

Descaling Powerstar AE-115 & AE-125

The electric tankless water heaters, Powerstar models AE115 and AE125 are high kilowatt electric tankless heaters that heat water on demand as the water passes through them. The modules inside consist of coiled elements that heat the water. The heating elements produce extreme heat inside the modules to heat the water on demand.

The heat that is produced by the heating elements in the modules sometimes counteracts with the mineral deposits in the water. If there is a high mineral content due to a hard water area then these mineral deposits known as "scale deposits" will over time attach themselves to the heating coils inside the modules.

All Bosch Powerstar electric tankless water heaters should never be descaled with any type of solution such as vinegar, muriatic acid, etc. The use of descalants flushed through the heater does not have much effect on the mineral deposits attached to the elements. Another point of trying to flush descalant through an electric tankless heater is that it will loosen some of the mineral deposits in the heater and will have a damaging effect on the flow transducer and other parts inside the tankless heater that detects the flow of water and will interrupt the signal to the circuit board itself.

The best protection against mineral deposits (scale) forming on the coils in the electric tankless heater is to check the quality of the water in your area before installing and if the water has a high mineral content then it is recommended to install a water softener or scale stopper system. The water softener or scale stopper will filter out almost all of the minerals and treat the water so the electric tankless water heater will have a longer life with less minerals building up inside.
Title: Re: Heatworks Water Heater KickStarter
Post by: Frost on January 24, 2014, 08:00:27 pm
This is not the kind of heating element what I mean.
It's intresting that the www.stiebel-eltron-usa.com (http://www.stiebel-eltron-usa.com) page shows only
the low power DHC-E devices from stiebel and all come without
the bare wire heating element.

Maximum of 12kW, this is ridiculous, I would never use a continuous flow
heater with such low output power <24kW.
I can't imagine that they work properly with only 12kW of heating power.
Either you need a high inlet temperature or the output flow rate will be
extreamly low. Ok, maybe Hawaii could be the right place.

For the DHC-E 12 they quote a maximum temperature increase
of only 36 degrees fahrenheit at 2.25GPM, that's only for people
who prefer to take cold showers :)


- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Here is a patent for an optimization of a bare wire
continuous flow heater.

http://www.google.com/patents/EP2597394A1?cl=en&hl=de (http://www.google.com/patents/EP2597394A1?cl=en&hl=de)

The aim is the optimization of the waterflow inside
the heating element to reduce the passive areas
within the cartridge.

Fig. 2 shows a cross-section of the bare wire heating element
Title: Re: Heatworks Water Heater KickStarter
Post by: sync on January 24, 2014, 08:11:34 pm
Inside those coils are the wire resistance heating elements. SE uses the outer pipe to slow down the degradation of those wire coils, but obviously they still need to be descaled.
And the reality is that here in Germany they are used without descaling. If they scale then they will fail due overheating as you wrote. But that's not the case. They ran for decades without failing.

For example Siemens wrote that no descaling is necessary (sorry German):
"Entkalkungssystem       keine Entkalkung erforderlich"
http://www.siemens-home.de/produktsuche/warmwasser/durchlauferhitzer/elektronische-durchlauferhitzer/DE18401.html?source=browse (http://www.siemens-home.de/produktsuche/warmwasser/durchlauferhitzer/elektronische-durchlauferhitzer/DE18401.html?source=browse)
-> Technische Daten
Title: Re: Heatworks Water Heater KickStarter
Post by: Frost on January 24, 2014, 08:58:52 pm
And the reality is that here in Germany they are used without descaling.

That's absolutely true.
I use continuous flow heaters for over 30 years now
and never had a problem with scaling.

Yes, the first heaters were crap, because you could
not control the outflow temperature.
So you had to mix cold water at the faucet to get
the right temperature.

With the new full microprocessor controlled heaters
like the Stiebel DHE SL which appeared on the market
around 10 years ago, that is now a thing of the past.

You can remote control the outflow temperature in
steps of 0.5 degrees Celsius (0.9 degrees Fahrenheit)
and the output flow rate in steps of 0.1 Liter per minute (0.026GPM).

The device is able to offer different wellness programs
with computer controlled flow and temperature curves
but this is only a gimmick that I never use.
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 24, 2014, 09:14:30 pm
Frost,
The limiting factor is the amount of current you can connect to one heating device at one time. UL here in the US limits it 48 amps, and I think CE, limits it to 50. So the larger "whole house" units are just two or more individual heaters in one package, with multiple power connections. You are correct about your assumptions about incoming water temp or flow. So if you needed 24kW say, then two of ours would suffice when piped in parallel.
As far as scaling, if the mineral content is low, then scaling is not a problem. However, that is not the case in much of the world, certainly not in the US.
Thanks,
Jerry
Title: Re: Heatworks Water Heater KickStarter
Post by: sync on January 24, 2014, 09:41:51 pm
Frost,
The limiting factor is the amount of current you can connect to one heating device at one time. UL here in the US limits it 48 amps, and I think CE, limits it to 50. So the larger "whole house" units are just two or more individual heaters in one package, with multiple power connections. You are correct about your assumptions about incoming water temp or flow. So if you needed 24kW say, then two of ours would suffice when piped in parallel.
We have three-phase electric power in our houses and apartments. Only some very old installation doesn't. My apartment has 3x36A@230V (25kW). I think it's the bare minimum by code. It's upgradeable to 3x63A (43kW) without rewiring. Plenty of electricity to burn. :) But I use natural gas for heating and warm water.

The biggest domestic electric water heaters are 27kW. One unit. They are connected to 3x40A.

Quote
As far as scaling, if the mineral content is low, then scaling is not a problem. However, that is not the case in much of the world, certainly not in the US.
In my region we have very high mineral content. We have scaling problems even with cold water. But not with bare wire heaters.
Title: Re: Heatworks Water Heater KickStarter
Post by: Frost on January 24, 2014, 09:54:15 pm
The limiting factor is the amount of current you can connect to one heating device at one time.

I know, thats mainly an US problem I think.

UL here in the US limits it 48 amps, and I think CE, limits it to 50.

That's not the main problem.
The circuit breaker in front of the heater is reatet with only 40 amps.
But in germany nearly every house and not only the house,
every distribution board of a dwelling unit, too
is connected with Three-phase electric power to the grid.
The result 230V*SQRT(3)~400V and this reduces the required
current.
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 24, 2014, 10:41:55 pm
Good feedback, thanks!
we plan on a 3 phase unit later this year.
Title: Re: Heatworks Water Heater KickStarter
Post by: Poe on January 26, 2014, 04:10:28 am
To Poe,
I find it hard to reply to someone who clearly has not read or understood the material and is suspicious of everything we state without the benefit of basic knowledge, so I won't.
If you (or anyone) want to learn more, please email me at info@isitechnology.com
Thanks,
Jerry

Emailed you without reply. 

I understand your trepidation, your story is quite common.

You developed a product without completely knowing your market.  Now you're trying to build a business unloading these things on an uneducated customer base by implying benefits.  I'm not saying it can't work.  Snake oil salesman made livings for centuries doing this stuff. 

My post hopefully educated some people.  If I got anything wrong or you see any fact that needs corrected, please point it out on this very public forum and I'll correct it with an appropriate apology.  Something tells me you're not willing to do the same.
Title: Re: Heatworks Water Heater KickStarter
Post by: ISI on January 26, 2014, 02:39:45 pm
Poe,
I checked my inbox, junk and spam folders and did not get an email from you. Please resend with EEVBLOG in the subject line.
I have spent over seven years researching this market and rightly take offense at your unfounded claims of snake oil salesmanship. Is it possible that you are trying to undermine us because you are a competitor?
Your claims generally unfounded, and please see this US DOE report for support on the big picture for tankless. http://energy.gov/energysaver/articles/tankless-or-demand-type-water-heaters (http://energy.gov/energysaver/articles/tankless-or-demand-type-water-heaters)

Far from being  a novelty item, there are over 13 million sold around the world each year, and our fellow bloggers from Germany that were discussing scaling can probably tell you that they are not a novelty in Europe

Do they, in your words, "suck"? Yes, and that is why I spent years developing a better one.

As far as your claims about heat pumps, where do the heat pumps get their heat? From the surrounding air. If they are in your house (they don't work well at temps less than 45 F, so people don't put them outside in NA), don't you have to replace that heat, which drives up your heating cost? Plus,since their recovery period is significantly longer, most people operate them in the hybrid mode, which uses archaic heating elements, and results in much lower efficiencies like conventional electric tank type. Pus they need to have their filters changed monthly and provide 55-60 galleon of water storage in the same envelope that an 8- gallon tank used to take, so there is a lot less actual hot water you can use.

As far as recirc systems, they costs about $100-200 per year to run, so if you don't care about energy savings (and since you told us you take showers at 7 GPM apparently you don't seem to care about saving water either) then you can certainly use them.

I think what really pains me is this comment;

"Your marketing is pretty devious.  It makes all kinds of implications, insinuations and just incorrect statements concerning your system in comparison to other heating systems.  Most of the time you're really spinning the numbers and making crazy assumptions behind the scenes."

I think you owe all of us specific and detailed supporting information behind this statement. I understand that this blog is meant to share information in an honest and professional manner, and I would appreciate it you would respond in kind.
BTW, what part of the world do you live?

Thanks,
Jerry
Title: Re: Heatworks Water Heater KickStarter
Post by: Lona_Joseph on January 15, 2020, 11:57:07 am
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