Author Topic: Heatworks Water Heater KickStarter  (Read 21483 times)

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Offline rrpilot

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Heatworks Water Heater KickStarter
« 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

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.
 

Offline mtdoc

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Re: Heatworks Water Heater KickStarter
« Reply #1 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 can put out 2.5 GPM using 7 kW.

As Dave would say: Fail :--
 

Offline Marco

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Re: Heatworks Water Heater KickStarter
« Reply #2 on: January 03, 2014, 12:04:57 am »
Getting high efficiency in heating is just a question of good insulation.
 

Offline plesa

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Re: Heatworks Water Heater KickStarter
« Reply #3 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

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?
« Last Edit: January 03, 2014, 12:10:55 am by plesa »
 

Offline fcb

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Re: Heatworks Water Heater KickStarter
« Reply #4 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.
 

Offline peter.mitchell

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Re: Heatworks Water Heater KickStarter
« Reply #5 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 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.
 

Offline mtdoc

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Re: Heatworks Water Heater KickStarter
« Reply #6 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 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.
 

Offline Jon86

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Re: Heatworks Water Heater KickStarter
« Reply #7 on: January 03, 2014, 12:49:40 am »
Quote
Direct electric resistance technology

 :-DD
Death, taxes and diode losses.
 

Lurch

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Re: Heatworks Water Heater KickStarter
« Reply #8 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.
 

Offline rrpilot

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Re: Heatworks Water Heater KickStarter
« Reply #9 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.
 

Offline sleemanj

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Re: Heatworks Water Heater KickStarter
« Reply #10 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...



Image from ADVRider, these types of quality electrical installations are common in South American countries.
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Offline Frost

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Re: Heatworks Water Heater KickStarter
« Reply #11 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/
 

Offline Maxlor

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Re: Heatworks Water Heater KickStarter
« Reply #12 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?
 

Lurch

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Re: Heatworks Water Heater KickStarter
« Reply #13 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.
 

Offline Rufus

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Re: Heatworks Water Heater KickStarter
« Reply #14 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.
 

Offline Frost

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Re: Heatworks Water Heater KickStarter
« Reply #15 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.
 

Online Psi

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Re: Heatworks Water Heater KickStarter
« Reply #16 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)
« Last Edit: January 03, 2014, 02:39:37 am by Psi »
Greek letter 'Psi' (not Pounds per Square Inch)
 

Offline gxti

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Re: Heatworks Water Heater KickStarter
« Reply #17 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.
 

Offline SeanB

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Re: Heatworks Water Heater KickStarter
« Reply #18 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.
 

Offline Alphatronique

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Re: Heatworks Water Heater KickStarter
« Reply #19 on: January 03, 2014, 05:12:34 pm »
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

« Last Edit: January 03, 2014, 05:21:25 pm by Alphatronique »
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Offline fcb

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Re: Heatworks Water Heater KickStarter
« Reply #20 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?
 

Offline Alphatronique

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Re: Heatworks Water Heater KickStarter
« Reply #21 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
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Offline fcb

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Re: Heatworks Water Heater KickStarter
« Reply #22 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?
 

Lurch

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Re: Heatworks Water Heater KickStarter
« Reply #23 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.
 

Offline fcb

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Re: Heatworks Water Heater KickStarter
« Reply #24 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.
 


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