What's inside a tankless water heater
HTML-код
- Опубликовано: 16 июл 2024
- Exploring what's inside a tankless water heater (also called on-demand, continuous flow, inline or instantaneous water heater). How does it work, what failed in it, could it be fixed? It's using a 3.5kW bare wire heater and a regulation with a microcontroller and a triac. The type is EIL 3 Premium made by Stiebel Eltron.
Please support my channel on Patreon:
/ diodegonewild
Instagram:
/ savage_danyk 
Наука
That heater has more processing power than my first computer did.
Probably more than the initial moon landing!
This simple programm could be done with a few lines of assembler on almost any realy small controller for sure...But the bold processors are to cheap today and and the programmers are too lazy to deal with assembler code too...
Have no clue why my comment that is has more than the moon l a n d e r did?
Utub is insane.
Nowndays a microcontroller that would outpace all the computing power of the 1950s costs about 5 cents and takes under a watt of power
Probably more cooling capacity (heat removal) as well.
This water heater shows many similarities between water flow and current flow, including the pressure drop tubing acting resistively. A great crossover assembly of electronics and "plumbing". Thanks for your insight!
Exactly my thoughts 😂 also reminded me of small and large bowels.
Except, current doesn't flow....
If this were used here in the UK, if it leaked any amount of voltage to ground up to 30ma it would trip the protection switch.
I'm guessing the company that makes this also advertises themselves as being environmentally friendly while making stuff that can't be repaired because they refuse to sell the part therefore increasing waste.
I suggest returning the waste back to the company's HQ.
If this were done as a safety measure, kW water heaters would be the type of device that I would completely accept that for.
You don't want your handyman repairing one for you.
Made in Germany, but the top text is in Polish and English, and analyzed in Czechia, true EU content ;p
Who would have thought that stuff like that was actually still being made in Gerrmany.
Fake ,probably made in china you see something made in country other than china you automatically start thinking it is safe
@@andreasu.3546 if there's anything I'd not get for 20 bucks on Aliexpress but made in countries with consumer protection and an (arguably) working judiciary system then it would be the water heater I use in my daily shower
It's because they are useful. Small single phase instant water heaters serve great in summer houses. You can leave them there even for wintertime, cause there is no big water tank like in a boiler, that can freeze up and explode. And it's never an easy job to fully empty that tank.
@@5Dale65 They are useful, absolute. It's just that such cheap home appliancese tend to be made in nearshoring countries like Hungary or Turkey (if not in China) these days.
EXACTLY the same thing happend to me a few years ago. I had the same or a very similar heater and the seal failed in the same way. I was thinking about just putting it back together with silicone, but ended up throwing the whole thing away. Obviously the design is flawed. Screw those manufactureres who dont sell replacement parts!
Lol id just superglue that thing and use it ONE LAST TIME.
@@VJETRA I thought the same thing, but plastic is sometimes tricky to glue. You need to know what kind of plastic the thing is made from
@@WolfmanDude well theres screw hold them together . the glue is just to seal that small bit
Design is not flawed. It "works" exactly as intended. For exactly how long was intended.
Still lovin’ the Catculator :D
They have a built-in abacus calculator, meow 😂
Always wondered how this type of hot water heater worked. Loved the schematic.
Get your cat a flat dish. The whiskers may get stressed when touching the edge of the bowl.
I love how the Catculator sits there judging you whilst you use it...
Seems reasonably well designed and constructed, those seals not being available is stupid though.
It's probably because of liability, can't have random people mess with a device like this where high voltage/ current & heat is this close to water.
They might sell spare parts to licensed companies though, i had my stiebel eltron repaired once after a surge (by an electrician).
@@timhartherz5652 All the fixing screws probably have to be tightened in the right order to the right torques too - like an engine block!
Could try to silicone it, worst case it just leaks again, depends on how high the pressure in the pipes is.
@@BitterCynical Worst case it leaks into the electric and the wall socket isn't properly grounded giving someone a good shock.
One can try, but the Manufacturer will reject any responsibility.
@@timhartherz5652 they can just write: to be serviced only by qualified personnel, no reason to not sell the seals except to make more money
Nice, I wish you had explained the Triac Optocoupler Controller circuit in more depth though.
We'd love a re-gasketing and testing video, like the transformer rewinding video :)
i would just apply some automotive flexseal used for oil pans, in case you have no matching OEM seal at hands.
@@rarbiart silicone gasket maker
Excellent video! I love these tear downs. Give kitty a petting from me! She's so cute.
He has a the most pronounced up-speak I’ve heard. I keep waiting for that last syllable on each sentence. 😂
8:24 i love your schematics ☺ thx DGW, another great video!
The heater is not "just" omitting cycles. Zero-crossing control (that's what the AC wave skipping is called) is actually the only thing allowed at these power levels! (Well, unless you have a fully power factor corrected supply, which is mighty expensive when we talk 3.8kW). Most electricity providers prohibit having more than 300-400W phase angle controlled (that's per mains phase entering the home), because of the non-sinusoidal load on the grid (that's in sync for all consumers on top of that).
I dont understand how it affects the provider wether you use one or the other when you're switching into a resistive load (harmonics ?)
May i ask you some sources to read about it ?
@@weistonaski6924 Switching on (or off) at the top of the voltage, creates transient (current-) spikes. So yes, harmonics reflecting back into the net.
Very cool. Been hoping someone would take one apart that I watch.
These instant heaters are commonplace in many developing countries because a gas heater system is way too expensive to build into a older house, even though it's cheaper in the long run. Most of the "suicide showers" here have no turns at all, the water floods a small chamber where there is a bare wire heater eating several kW from the mains.
Gas plumbing shouldn't be done new anyway, as methane gas causes climate change. Besides, every use for gas has better alternatives now.
For hot water, use a hot water heat pump.
For heating the home, use a heat pump.
For cooking, use an induction stove.
The price is changing too. Solar is absurdly cheap now, and battery prices are dropping quickly.
Because Germany is a developing country???
These are very common in Germany and as weird as it might sound, they are very safe if installed correctly.
They are also Common in developed Countries. These small Units are usually used for sinks which are rarely used and to far away from the Central Boiler to justify a hot Water Pipe.
For some reason I have a 36kw unit in my Bathroom and a 17kw one in my Kitchen while the room heating is fueled by the waste Heat from an Incinerator.
Intressting little device. I've never seen a single phase continuous flow heater.
The ones we have here in Germany are usually 3 phase and use between 18 and 33kw.
33Kw For what? An entire apartment building?
@@MrTurboturbine instantaneous water heater require a lot of power. 2 kW tank heater will heat 100 liters of water after 6 hours, and 33 kw heater will heat it in seconds
Yes, with 3.5kW, the water is barely warm with a fully opened tap.
i see quite a number of them in german office buildings. it provides "warmed up" water for lavatory sinks.
@@MrTurboturbine the power required really depends on water input temperature, it gets really cold in germany
Thanks!
I love that screwdriver probe!🤩
3:15 - We have buy a Stiebel Eltron too, with 3 phases 11kW/13kW heater inside and electronic temperature settings.
An other advantage is, that the Calcium oxide inside of the water can not stuck at the surface of this wires. This makes it very endurable.
My female cat is doing the same, take a bit of food, put it at the side at the ground and eat it there. 🙂 I always have to clean the ground with Isopropanol+Water spray and some toilet paper after she is ready.
Nice that we could see the inside of the water heater.
That Stiebel Eltron does not sell this silicone seal is bad, there should be a law for the repairability of this devices.
You can try to use flat dish for your cat, probably cat instinct tells them avoid to put their head in such a holes
@@user-ui6xt4fd1f - I will try it.
It is NOT calcium oxide! It is calcium carbonate. Very basic chemistry, even a 13 year old should know this.
@@mernokallat645 - You are right, it is CaCO3. Possibly with 13 I did know it.
cool stuff.
Thanks for sharing, I never come across this kind of heaters. I thought they were not even sold in EU.
They are the best way do get hot water if you have a summer house
I suspect the additional back and forth tubing also allows some mixing so the water coming out is of a uniform temperature instead of having hot and cold areas.
We need more of your thoughts
Nice 👍👍, I guess you could try to seal it using some RTV silicone!
Or 3D print
Mains heater/wiring right in the water and it just relies on resistance of water.
Would never have thought of that.
I assumed it would be some metal block that has got an insulated heater attached to it, the water then just flows thru the hot metal part.
Very similar concept to the electric showers found in latin america. The difference is that this one has electronics, while the showers are just a membrane, two resistors in water, and the power selector.
It is very safe, when installed with proper grounding + GFCI + dedicated breaker.
Looks like the seal could be 3D printed using TPU, though drawing it would be tough. It could be 3D scanned tho.
And I'm not sure about the thermal stability of TPU in hot water 😕
just take a photo of the seal with banana for scale, then import this photo to a 3d program and design around it
I thought the same. Ir to make a 3D printed mould for making silicone seal. But likely not worth the time.
step 1 put the cover with the groove in the regular scanner with a ruler beside it for scale, step 2 cad, step 3 print in tpu if it can handle it or print a mold and inject gasket/high temp silicon
@@taist5400 This wasn't meant to be open anyway just glue the cap with silicone sealant, doesn't even need high temperature.
Place the seal on a flatbed scanner with a ruler next to it.
TPU would indeed not hold up to the temperature, but as I've replied to someone else: TPU wouldn't hold up to the heat, but you could definitely create a mould in PVA filament, cast with silicone rubber, and dissolve the mould.
Wow, what a powerful microcontroller for such a simple task!
Phase angle control isn't possible, because the optocoupler has zero crossing detection build in!
Such a pretty much simple device has more processing power then some peoples first computer ☠️
Trypophobic people may hate this video 😂
At this point, absolutely everything seems to have its phobia and filia...
It was the first thing I thought of when I saw the thumbnail. Too many little holes!! 😅😂
@@DiodeGoneWildBased diode
Whyyyyyy do youuuuu streeeeetch all youuuuur wooooooords?
You must at least be able to shorten them? Or is it a trademark?
@@TheDutchShepherdIRC he's from East Europe so he's got quite an accent, and it just happen to sound like he's lengthening his word 😄
Also, this is a bloody complex thing, most of the suicide showers directly switch the mains to the heater just using the water pressure alone and a piston.
How is this complex? It's just a simple feedback regulated heater
This one is typical of an electric shower.
Takže takto vyzerá vnútri prietokový ohrievač, už dlhšiu dobu som bol zvedavý ako také niečo pracuje, ale bol som lenivý si o tom niečo nájsť :), takže ďakujem za toto video.
I wonder if you could use liquid gasket maker to fix the seals
Greetings from Poland. Some time ago I found a tiny 7,5kW heater in the garbage, powered by 380-400V AC voltage. He worked in and old apartament.
Hi
Thx for another awesome vid, its always exciting when you post a new one. Why do cats do that? I have to line the floor with newspaper around the cats bowls.
Can you use Gasket set to reassemble the heater.
This is called a "Durchlauferhitzer" in German, which directly translates to "flow-through heater".
The Czech name of it "průtokový ohřívač" would also directly translate to "flow-through heater".
Wonder if a 3d printed tpu seal would work as a replacement
Interesting. I need one for 24V though. I might buy one and use a resistance wire.
I don’t think they make them for 24V. To have the same power as the one in the video, you would need at least 150 amps of 24V.
You might need as much as a kiloampere if you wanted a hot output with really cold supply water, even if you had a low-flow energy saving showerhead.
@@deltab9768 I have solar panels and AGM batteries, which can sustain 120A for hours. With a NiCr resistance wire instead of the heating elements, I might get enough heat to take a shower. However, this project switched my creativity on. Instead of using a high power heater, I might use a normal one, and make the water circulate in a tank. A 3 kW heater like these, erogate about 300 W at 24 V, and with a small pump, I can heat a 100 Liter tank up to 60°C in a matter of hours, with relatively small currents (10-15 A). We have used this system at work and it works great, when power availability is limited. You switch it on over night and have all day hot water.
At first I thought you were wrong. A well-known German company makes something like that?
But after a bit of googling you are right. It is a "bare wire heater" and as you say: if the water path is long enough, there are no problems with ground currents. Learned something new again.
Nice teardown! How many pins on the MCU are actually in use? There seem to be so few things it really needs to do.
As others have mentioned, you could just use silicone sealant to make gaskets yourself.
I wonder why they didn't just go for an "electrode heater" design if they weren't isolating the heating element anyway - that way there's no possibility of the element overheating if it's not covered with water.
The electrode heater design has significantly more current passing through the water, and some small amount of electrolysis corrosion can happen even on AC.
Not to mention the power would depend on the water conductivity in that situation.
Surely this type of heater would trip an RCD with bare elements?
No, the leakage current is way less than 30mA.
Very interesting design features. A pity the gaskets were not up for the (mostly modest) task.
So this is a safe and up to european standards suicide heater, which is just a better developed version of the suicide shower heads from Brazil. I like that 😂
👍
DGW, what happens to power dissipated in the ground circuit? Surely some current is lost in the ground loop. Do these things sork with GFCIs?
The ground leakage current is surely way less than the 30mA needed to trip a typical GFCI.
Hi !
is it the new sui*ide bath? Lol
it's surprising if it doesn't trigger the differential switch at the threshold of 15 mA
What happens to scale on the resistance?
if the water is softened, it becomes more conductive by adding Na+ and therefore there is a risk of phase and earth conduction.
could you measure the current leakage to earth?
When the water is turned on the flow of the water pulls the plunger in to make the contacts for the heating element.
M glad I worked that out in my head before I seen the membrane. Nice.
I wonder if you could 3D print a replacement gasket out of TPU. As long as the water temperature doesn't exceed 80C, it should be fine.
can you please make few epiodes on washing machines boards and electrical oven
Those gasket seals look like they could be 3D printed with TPU
TPU wouldn't hold up to the heat, but you could definitely create a mould in PVA filament, cast with silicone rubber, and dissolve the mould.
My dad has a similar device branded "clage" that's made in England apparently, and it is as simple and dumb as can possible be, it only has 2 micro-switches and a heating resistor and that's it, the temperature is regulated by a screw that regulates the water flow. Honestly its a pile of "rubish".
No chance to buy sealings? I wonder if these could be made by scanning the block and then 3D printing new ones out of a thermo-curing elastomer.
Some of those Stiebel Eltron instant heaters have electronic sensing system rather than (or on top of) hydraulic, this one may be an example. These can work with pre-heated water, which is useful with a storage water heater being the primary water heating device, with the instant heater active only when the hot water from the tank hasn't reached the tap yet, or got depleted.
I'd love to see the electronics reverse-engineered. It's surprisingly advanced, using a STM... not sure why.
Only seen these in the uk and find it terrifying when they are in the shower, and I am no stranger to 220v kisses.
Impressive to think this Triac cause such little voltage drop, it can switch 16 amps with no heatsink required.
It has a heatsink cooled by the water.
@@DiodeGoneWild You're right of course, I didn't notice it but the cooling block is clearly visible at 2:25.
Megger tested?
Only cycles, no angles? :)
Yes, because phase-cutting produces harmonic distortion and radio interference (which compliant phase-angle controllers have to filter).
In light dimmers those are necessary evils (to avoid creating unacceptable flicker), but there's no need to go to such trouble in a heater like this.
A Czech valve in a German water heater. These devices are just OTT.
An MCU at all fells like overkill, but a stm32 is over-overkill
It May be Overkill, but If they Order a bazillion of identical Pre Programmed μC which can be used for all Models by adding the necessary Parts it may be still cheaper then a smaller one or doing the Same with Logic.
Also the 1€ μC doesn't contribute much to the price of the Unit.
@@walterbishop2Stm's are rather expensive though. Lots of drastically cheaper options. Although maybe they got a good deal.
I'm a bit disappointed that they didn't control the power in thirds (obviously the heater would then need to have three full-voltage segments wound with thinner wire, so whether it'd be durable enough is another question; but obviously if they really cared about durability, they'd sell replacement gaskets).
where is the schematic of the pcb? :(
I guess this proofs that a hair dryer droppen in your bath wont kill you
thanks, but i'll stick to my 18kW gas-powered one. it works good enough
Brother I have three old Soviet transistor name of the transistor are TKD 165-80 and TKD 165-250 and TKD 265-250 I want to donate to you but I don't know how to donate for more information reply have a nice day comrade
Wow that's like those showers you see in certain countries, I don't think that would be allowed here...
08:23 PacMan schematic ............. This device is a slightly safer death shower which Clive investigated. Great work thanks
32kb of flash just to make current flow thru a wire
And I thought the 16kb to run my electric toothbrush was stupid enough
Humanity is doomed
Using 100Bn neurons for some primitive work?
What does this mean: grounded?
Parts someon may touch, here the water connectors, are wired to the world, so there can't be voltage in-between, nobody can be shocked. One power connector is on the same potential, by the way. But these days a third wire is used.
By the way, it's actually possible to have a ground free socket, where someone could touch one power connector at a time. But the existing power grid is grounded. I'm glad you asked.
@@timtim8468 Thank you for helping.
Why using an optotriac when the microcontroller is not powered by an insulated power supply ?
When the microcontroller is powered using a bridge rectified capacitive dropper, it is referenced to a wrong point. It can't control the triac directly.
their boilers also suck :/ replaced lots of heating elements who were just disolved
so because it uses a bare wire heater, it's a suicide shower in a box. i was expecting to see a sheathed heating element instead
How come the naked wires are immersed in the water to heat it? are you mistaken or I didn't get it? you said the copper wires are in contact with water!
Read the text on screen 3:15
Decided to take bath with cold water except using electric heater
Now let's compare this safe (and necessarily complex) design with some Chinese ones!
both are suicide showers in boxes because they use bare wire heaters with no insulation
i was shocked seeing how a device that heats water with live wire like this one can be safe!
Can you not use the old seal and pour epoxy to make a mold? Once the epoxy sets, pull the old seal out and use the cavity to pour silicon in it.
When the silicone sets the next day, you have a new gasket. Make more if needed.
I wonder how well those would sell
3D printing would work too using TPU
@@sakurojason TPU leaks like a sieve.
@@drobotk Who said anything about selling? It's how others make gaskets for repair jobs.
@@objection_your_honor Then I got a better idea. You could 3D print an injection mold and mold a gasket out of silicone.
Please Review - 12V 2A CCTV Camera Adapter - Black
For a tankless water heater this really doesn’t use as much power as I would have expected. In America a typical tank water heater uses 4500 watts while tankless ones use on average around 10-20 kilowatts.
6:35 kitty!
Voltage nameplates cannot be trusted, because when heater is running, the mains voltage drops. Therefore, Real Watts = {new dropped voltage} x Current
Water heater is more complex than an automatic transmission.
Nothing is more complex than an automatic transmission
I'd just use some good old RTV gasket maker problem solved
Kinda like those dodgy showers😂
4:25 What an absolute mark of bad quality and bad business practices to not be able to offer spare parts for your products. wouldn't bother further with such a brand.
The sad reality is almost every company is going slowly towards this.
What is the cat's name? I don't want to call him Catculator, lol. Those extra channels make fitting another seal more difficult.
Her name is Veritáska ;)
Its a tankless job but someone gotta do it
secret Life of the washing machine
much more secure than "suicide shower"
So what college are you teaching at
Seems like electrolysis would degrade the Heating element Over time.
with an AC current, the electrolytic effect mostly cancels out.
BigClive, Zerobrain
Any air or bubble in your water are going to be problematic
Looks failure prone.
Won't sell service parts? Welcome to my blacklist, Stiebel-Eltron!
Here in North America, we can only dream of such things.
Not really. Most european ones work on 230V 50Hz. They will work fine on 240V 60Hz as well.
@@5Dale65 Sure. All the houses are full of 240V outlets.
@@ozzymandius666Most American houses have 2 separate phases in them. It is fairly standard practice to connect them together to get 240V for AC units and some other gear.
@@memejeff Sure. All the houses are full of 240V outlets
@@ozzymandius666obviously your house doesn't need to be "full of 240V sockets", of course 1 or 2, AC/this heater is enough.
Wot aböutte æ Tankful wœter heaτeř?
Máš otravnou intonaci hlasu.
Tankless?It has lot of tiny tanks