Electric Shower Head Teardown Makes Us Wince

We have bought some really amazing stuff from the Chinese online shops. We’ve also bought stuff that was… less than satisfactory, let’s say. At the prices you pay, you usually just chalk up the bad stuff as a cost of doing business. But [DiodeGoneWild] has a teardown of something that could be very dangerous if it wasn’t up to snuff: an electrically heated shower head. He says they are common in Latin America and have the nickname “suicide showers.”

We’ve seen the cute showerheads that change color, but those take batteries. What we are talking about here connects to the 220V main and draws 30A to instantly heat your shower water. Environmentally, that’s great since you don’t have a tank of water you keep heating and reheating just in case you need hot water. But you wouldn’t throw an AC radio in the tub, so you have to wonder just how safely this thing’s built. Well, you don’t have to wonder, because the videos below are going to show us.

That’s nothing, a look at the design takes a comical turn. Immersion heaters already exist but this design shares nothing with proven methods. The green wire which is a neutral has no place to fasten inside the plastic body. It just goes inside, connects to nothing, while being exposed in the path of the water, presumably to keep water that was too conductive from shocking you. The heating element itself is little more than two coils of (presumably) nichrome wire exposed directly to the water.

There is a low tech pressure switch to prevent the coils from powering up if there’s not enough water pressure. You hope that prevents the unit from bursting into flames.

The shower head is marked 5400 watts — basic math for the 220 V at 30 A has us expecting more like 6600. Based on actual measurements, it looks like the high power coil is 9 ohms and you’ll see in the video, he does the math not only to look at the power consumed but also how much power it should take to heat up water in an instant water heater arrangement like this. It was interesting to watch him measure the flow rate of the shower with a low tech method. The final answer is that the head really needs to draw much more power to really give you a hot shower.

In part 2 below he actually wires the thing up. Having the connections near the leaking water gave us the willies. We also knew it was a bad sign when his GFI tripped from excessive ground current. Turns out, the ground current was just under 200 mA. If that doesn’t scare you, perhaps where he measures 10V in the surrounding water pipes will. There’s even voltage measurable in the shower water although at pretty low current. And while it might not be enough power to really warm the water enough, it does seem to work.

We’ll stick with our passive shower head, thank you. We’ve seen homebrew versions of this that don’t try to heat the water instantly, which is probably a more forgiving arrangement. But there are plenty of easier ways to hack your shower.

141 thoughts on “Electric Shower Head Teardown Makes Us Wince

  1. >”Environmentally, that’s great since you don’t have a tank of water you keep heating and reheating ”

    Environmentally, electric showers and other “instant hot water” appliances aren’t great because they increase the load variation on the grid, which is met by the least efficient and most polluting fast ramping powerplants. Often diesel engines are used to smooth out the peaks in demand, because not even gas turbines will react fast enough.

          1. Really ?
            Looked at conjunction of; form factor for the power level, radiative transfer and themal conduction issues, cost effectiveness ie. Don’t forget sum of capital cost in $ & time for manufacture, service and maintenance equivalent to comparative energy loss in operation at recognised $/energy exchange rate whilst appreciating importance of net present costing for proper analysis… Eg resistive very simple with negligible losses vs heat pump infrastructure semiconductor or fluid or ‘something else’ Which approach would you want either in shower head or piping leading to it, then what extra would you pay for a more complex setup for what difference in energy loss for outcome ?

          2. Heat pump water heater cost 5 to 10 times more than a resistive one which would be a bit of a problem in the market these are sold in.
            Even in places like the US and Europe the upfront cost is often considered too much esp in the US since natural gas is cheap.
            Plus they need more airflow since they’re getting the heat from the surrounding air.
            The cooling is a plus in the summer if it’s located in a closet or some somewhere shared with the conditioned space.
            If it’s in a garage or an external closet the added cold air goes to waste in the summer and if it’s smart enough it’ll operate as a standard resistive heater for most of the winter.

          3. These are Commercial Off-The-Shelf, you can buy one today. They sort of make sense if you’re in Manhattan and paying through the nose for power, and also in a situation where gas just isn’t going to work. Otherwise it’s a borderline idea at best.

          4. Heat pump prices are coming down fast, and a heat pump combined with a storage boiler allows you to take cheap off-peak electricity to advantage.

            That’s something the insta-boilers are bad for. When everyone’s taking a hot shower, the electricity prices go up.

        1. Just gotten through reading about a graphene-ink based water heater, and surface area, and flow rate play an important part. Shame microwaves is only about 64% efficient though.

          1. Jokes aside Gates’ mini nuclear power plants might do more to offset carbon emissions then all the EVs and self driving cars ever could hope to and maybe even more than solar.
            On self driving cars they can actually greatly increase carbon emissions if they’re used to replace lightweight rail or even scooters or motorcycles.

          1. Hmm, sure and maybe collect Banana and Brazil nut waste in a suitable ‘pile’ around a heat-exchanger pre-heating the cold water feed for the shower heater. A sizable amount of Potassium-40 and Radium-226 might just do something to offset electrical consumption. May as well also put in heat exchanger to collect warm discharge from shower and kitchen too – watch the kids compete when you set the shower heater to recognise the kids RFID or pin to get a prize using least electricity – great way to teach logistics. Het, then all that extra brain function needs more food which means more warm water kitchen waste – feedback/controls galore :D

          2. I know you were joking, but district heating systems kinda-sorta do that and they’re very popular and widely used here in Finland; they pump hot water from the various power-plants’ cooling systems around, covering a large number of housings and providing them with useable, hot water on the cheap. The power-plants, when running, will produce hot water anyways, so it makes sense for them, too, to make some extra money out of it. It’s a win-win for both. Obviously, they don’t pump contaminated water around, but they have heat-exchange systems there that transfer the heat from the contaminated water to the drinking water that is then pumped around.

          1. Of course you could but, at what frequency for max efficiency in comparable form factor ?
            If at not at mains frequency then cost of conversion, at any frequency what of power factor ?
            See my post in reply to Simon Ludborzs for more general issues too…

      1. Hmm. Resistive heating turns 100% of the energy into heat. As far as I have ever seen, you can’t do any better than that. If you use hydro or wind power it can’t be beat. Otherwise a heat pump is better, but it doesn’t convert some mechanical or chemical energy into heat, it harvests heat thermodynamically from a difference in temperature and is in a different category. In the over-all energy budget, I think using a heat pump with hydro is like using hydro to turn a windmill to get power for heat.

          1. Yes, and that takes work. If you can also use the I times R and mechanical heat (put all that on the outside of the fridge = inside the house). What are real-world efficiencies? I mean in power consumed versus heating.

          2. It takes work yes, but the heat it transports doesn’t all come from the electricity, so it’s effectively more than 100% efficient to the householder. You put 1000W in, get 3 or 4000W out… Considering just the house, it’s not a closed system, considering the planet, it is, but the extra comes mostly from insolation, and whatever other sources are dumping heat into the nearby air, like your neighbour warming his car up.

            I can’t justify one economically here, because air sourced pump would only be good 2 months a year and a geosourced one would have to be drilled pretty deep. (Also figure they only work if you’re the only one in the neighbourhood with one, unless it’s a more spread out neighbourhood.) … and I pay less than a quarter the cost of electricity for natural gas.

          3. >”because air sourced pump would only be good 2 months a year”

            Where do you live? The north pole?

            Good air source heat pumps work with decent CoP down to -5 C.

    1. Electricity peaks are smoothed by any means available.
      Water power plants can often be started very fast. There are even some storage plants with 2 lakes with a height difference in between and a turbine pump combination.
      It generates electricity when demand is high, and pumps the water back to the upper lake during periods of excess electricity. One of such plants is with the lakes “Lac Blanc” and “Lac Noir” in France. (English Wikipedia has no mention of the power plant)

      Some other methods in:
      Surprisingly the diesel powered generators are also mentioned and “privately owned” ???

      1. I lived in Brazil for a couple years… 75% of their power is hydroelectric.

        They actually upgraded the local Furnas plant on the Rio Grande in Minas Gerais while I lived there roughly doubling it’s output (from when it was originally installed in the 1950-60’s)

        1. Hydroelectric power is unfortunately not expandable. All the good rivers are already dammed, and there’s environmental consequences of building more artificial lakes, such as methane emissions from the covered up land.

    2. Completely INCORRECT, ever heard of batteries and capacitors? Batteries are chemical reactors with massive capacity but slow reaction, capacitors are suuuper fast, can charge and release energy ON DEMAND, so you combine both and you get a great power peak solution. A battery may not kill you a capacitor will broil you in a microsecond, don’t you believe it? Touch a 12 volt battery and ground yourself, you only will get a jolt that is it, now open your microwave and touch the capacitor… you will be in heaven even before you touch the ground.

        1. Years ago we had a vaporizer that had two electrodes hanging into water in a large glass jar, and the jar sat in a metal bucket that surrounded the bottom half. The electrodes were part of a Bakelite cover that screwed on the bottle. The steam port had a small tub below it for some Vicks Vap-O-Rub.

      1. Even rich people in Brazil use them almost universally…. they aren’t that dangerous. Poor people don’t have them as they often can’t afford power, so just have a tank of their room and they take their showers in the evening after the tank has warmed in the sun.

        The real suicide shower is the older ones that are occasionally still used where these is no electricity… its an alcohol burner in the shower head, if it flips/spills over you’re on fire… at least you have water nearby….


        We had this type:

      1. AZTRAPH… yes they overheat, if there is an air bubble inside the head it will overheat and brake the resistor, that is why you should start with cold water “FIRST” then once you have even flow, THEN you select the water temperature, because if you leave the selected temperature on then you start the flow, there is a high likelihood there is just air on the head and that is when it OVERHEATS, once the water flows first and the heater 2nd then YOU are right, it is just matter of sequence.

    1. not really… so they get warm, as well as the connection block and the wires in the wall and the duse in the fusebox. But all that is negligible compared to the power in the heating element itself. So who cares.

      Regarding the youtube videos of people visiting a foreign country, taking one of these showers and then in shock and horror film these kind of shower heads. And while viewing these vids I’ve been wondering that if they really are so dangerous… then why do they still exist. So therefore I assume there is something wrong with the user/observers… of these showers. It is claimed by some that they feel a tingling sensation when they stand underneath these showers, somehow I can imagine that.

      But the natives they must feel this too… and if they do.. these showers must be horrible and therefore the design would die out. But normally the natives are much smaller then the tourists and because the tourists are taller they stand closer to the showerhead, making better electrical contact. We all know that the stream of water isn’t constant any more when it hit the floor, it is broken up into droplets and droplets don’t conducts, streams do.
      So when you are tall you are standing in a stream of electrically conductive water and feel the tingling sensation. But if you are small, the water is no longer a stream when it hits you and therefore current can’t flow.

      In other words… the shower is (kind of) safe when used properly (with enough distance between shower head and the users head). Something that is explained in the second video at around 14 minutes.

      Now I’m not saying that these are the safest showerheads around, please stay away from them as far as possible. But what I am saying is that these showerheads (if connected properly and used as intended) aren’t as lethal as everyone wants you to believe. You just need to know how to use them, like everyone knows that you must not put your hand into a working toaster or blender.

      This video only confirms that it is good to have (safety) regulations for these kind of things the bad thing is that everyone can buy these devices over the internet, therefore importing them and bypassing all regulations.

      1. Some time ago I saw a documentary about stealing electricity in “poor regions”.
        Some of the people there make a living as electricians by modifying wiring for other people in the neighborhood. A handfull of them get electrocuted each year.
        This always happens to “the stupid guy” and never to “the smart guy” which they consider to be themself.
        The value of a human life is not a constant. It depends a lot on the year you are born, the region you live in and the level you’ve reached in Maslov’s pyramid.

        1. Some time early 1990’s my business was approached by a co called Lexmin from India, the CEO was exploring someone in Australia to critique their products in terms of design, efficacy, safety and approvals for entry into the Australian market and as stepping to Europe and USA. He had lots of varied stats in respect of power theft around India’s cities. Turns out approx 5000 people die each year climbing up power poles attaching car battery jumper leads to a jumble of 3-phase lines to power their single phase fridges and cookers causing all sorts of power drop outs and massive surges too.
          The CEO claimed his entry path was simple but, the reality turned out hugely officious with multiple layers of beaurecracy then the catch – had to ‘assign’ some 50% of the trading co (paid for by the O/seas firm) to local control – all that killed exporting to India or even making 80% of product there :/
          Made this proof of concept unit specially to suit very wide voltage fluctuations…

          1. When I have been in India (Goa) for holidays the most observed “power fluctuation” was “off”, several times/day for something like 10mins to 1hr. And nearly every shop or place I stayed had such an inverter together with a truck battery. Normally powering one or several lights/room and the ceiling fan. Which of course is even more important when you can not use the air condition.

          2. Hmm thanks Martin,
            I had friends come back from Goa some 12yrs back without noticing power fluctuation issues, though they were at main hotels with sizable backups I think, when was your experience in Goa for interest ?

        2. When I visited a church mission in Colombia 25 years ago.
          They said that they paid their electric bill to set an example to their neighbors in the barrio.
          One month they forgot to pay, and the electric company cut their power.
          While they went “downtown” to pay the bill, one of their neighbors (without their permission) climbed the pole and reattached the wires!

          I really wish I had take a picture of a power pole in a newer barrio (invasio~n) with about 30 wires radiating from it!

      2. That is why you have to “GROUND PROPERLY THE GREEN WIRE” that wire is in “DIRECT” contact with the water, the other two (current and neutral) are “NOT” in contact with the water at any moment that is why they are “NOT” dangerous, (electricity goes to shorter route, so if the wire is in the water, it goes there, that is the shorter way, as opposed to escaping with the water outside, only when the green wire is not plugged to grawnd is that a VERY LOW voltage escapes with the water hence the tingling sensation) then everything else is just NON CONDUCTIVE PLASTIC that is why they are so safe and functional. GREAT product considering the cost benefit/efficiency. That is the principle of Benjamin Franklin with “LIGHTNING’ it will discharge in whatever is usually taller from the earth.

    2. Unfortunately, I’ve seen something similar that drew power only near the top of the sinusoid, the peak was pretty high whilst the RMS low averaging a bit under some 15 Amp overall. Not an appropriate circumstance at all. Geesh – just goes to show there are risks in so many places when the uneducated, ill-informed and those incapable of caring/considering of consequences produce dangerous goods :/

      In another case a friend who runs an EMC/RFI lab in Western Australia (240v) was approached to test a ‘power splitter’ so Americans could supposedly make coffee and toast their breakfast bread at the same time off a 115v 15 Amp supply, ugh – basic time function analysis fail. Suffice to say the ‘inventor’ missed the core issue…

        1. Indeed that’s the way to go and especially so within the last decade or so with variants of higher capacity Li ion, faster charging techniques etc Unfortunately the ‘inventor’ back then was so emotionally focused on his ill-thought through power splitting approach and my friend wasn’t comfortable with the inventors self-aggrandizement in terms of any challenge, it died a quick death…

    3. YOU CRImier…. the AWG (thickness of the wire) is 10 gauge so to answer your question, touch it when plugged, you will find out if it is capable of 30A, just to tell you the braker has to be 40A, 20A brakes all the time, 30A ok in low, so, so in high (not for too long) 40A no problems.

  2. do houses still have hot water tanks in north america? In the UK combi-boilers are the common household heating appliance, gas fired, instant water heater. In my house the boiler is sized a little larger than usual so it can also heat water for the shower while running heating. Most UK households run electric showers but obviously not suicide showers, and these are on there own circuit and breaker as they usually draw around 40A at 240v

    1. Combi-boilers seem to be a very European thing (probably because we have natural gas networks?). My American friends all have big electric water heaters. I have an electric boiler for water & showers and a city-wide central heating system that pipes around hot water to warm up all the houses.

    2. We do. We feed that hot water through uninsulated PEX or copper tubing for many feet running through concrete slabs or exterior subfloors. Most of the time this is because it’s the cheapest way for developers building out communities of spec homes or condos to get the job done.

      Of course you can retrofit a few tankless heaters throughout the house. The tankless heaters are about 2x the cost of tank heaters, and then another 4x for the various licensed contractors to run gas/electric and plumbing along with permitting. Sometimes local utilities run incentive programs to help with the cost to improve efficiency. However we’re focused on home equity here and $5000 sunk into a more efficient water heating system doesn’t look as sexy to prospective home buyers as new kitchen counters or solar.

      So we don’t really do tankless, and instead think up ridiculous stopgaps like this: https://www.homedepot.com/p/Watts-Hot-Water-Recirculating-System-with-Built-In-Timer-0955800/100426993

    3. Denis… in USA the selection of tank or tankless water heaters at home is up to the decision of the owner of the house, so tank water heaters are usually cheaper than good quality tankless heaters, this is the country of options, you can go tank, tankless, then within those options you could go: natural gas, propane gas, methane gas, electric (many configurations), etc, USA is the country of options in almost everything, like 30 to 50 different cereals, same in soaps, sodas, supermarkets, I have like 10 different supermarkets in a 5 mile radios, specially in NY and California, other states don’t have that many options, etc, etc, etc. you get the picture.

  3. “green wire which is a neutral”….. sure it is, if you happen to be a redneck diy homeowner.

    To a professional electrician, it’s (in the USA), the neutral is always the white wire.
    The green wire (ground) is always carried back to the main panel and bonded to the ground bus bar
    (that will have an ‘earthing’ ground, and also be connected to the service entrance incoming neutral).

    1. …in the UK everybody used to know that black was neutral (red live), until we were forced to change to the EU system (blue neutral, brown live). Now you have to know both if you encounter any older wiring.

      1. And? Other countries changed color coding too. Standards always evolve. As a scrapper i come across really old (pre-WW2) wiring that has a totally different scheme or none at all.

        IIRC the blue-brown-green/yellow scheme was devised so you can still make out the different wires if you happen to be colourblind.

        1. until you move to America where black is live white is neutral and earth is just bare copper in the jacket – it’s supposed to be so if a mouse chews the wires, hopefully they touch the bare earth and not each other

          1. I’m fairly certain that the EU is the only region where the blue/brown/green-yellow has been fully adopted, even if it was intended to be an international standard.

            My employer has multiple variants of the equipment we build, based on the intended destination, often the mains cord and plug being the majority of the difference between them.

      2. I think here in Austria it was red (PE), black (L) and grey (N) before we got black (or brown), blue and yellow-green. The change must have been sometimes in the 1960ies or 1970ies, long before the EU even existed. So, yes, when you encounter older installations you also have to deal with different color codes. If you are in doubt, don’t trust but measure.

    2. Wow. That’s a lot of standards. And… they all are counter-intuitive and therefore suck!

      Ok. To a person who has actually learned the standard any standard will do so long as it is followed consistently. Also, obviously the concepts of heat and electricity are not the same thing. But…

      What do we often call the ‘live’ wire? Hot. There is a natural connection between electricity and heat in most people’s minds, even ones who are mostly ignorant about electrical safety. Also, there is a connection which very well may be hard-coded into our brains, developed in our early days of harnessing fire between hot and colors such as red, orange, yellow and to a lesser extent even white. Ask a person who has never learned any color codes which one they think is the live wire and those are the colors they are going to pick.

      Meanwhile, black, brown and blue.. we will naturally associate those with water and earth which are cold.

      WTF were these people thinking when they came up with these standards? Were they trying to maximize the body count?!?!

      The only thing anyone of them ever got right was the standard of green for earth-ground.

  4. Those are Lorenzetti clones, the most falsified Brazilian product. Usually, the bathrooms have ground on the shower plug, although it is not recommended to use plugs cause current can pass 20A, the Manufactories usually recommend direct connection.

    A sealed resistance model is used when you have GFI it calls “quatro estaçoes” but it can cost $100 while these cheap models can be easily found by $10.

    The whole pipe is build of plastic including the shower valve. At the south of the country where it is colder they use the gas shower, here temperature rarely drops below 20 degrees Celsius. It commonly uses external switches, so the person rarely has direct contact with the shower when it is alive.

    Portuguese and Spanish are used at the manuals, although with some errors, at least with Portuguese words.

  5. I don’t know about Costa Rico or Nicaragua, but I remember my dad telling me that Brazil didn’t use an earth ground in the electrical grid. Without an earth ground, there is no return path for a electricity to take back to the source, so if there was a failure, you would be completely safe. That’s counter intuitive here in the U.S. were we use a common earth ground. the upshot is that if you touch a single leg of the main in Brazil, you wont get shocked unless you touch the other side of the main, everything else is safe. But I’m still not going to test that theory.
    I have been trying to find more “current” information about this, anyone got a lead on this? My information is from 40 years ago.

    1. I’m not sure that’s how it works… The ground has a voltage of 0 or “neutral” voltage. Your active has a non 0 voltage, either positive or negative. It is the relative difference in voltage that causes electricity to flow. If you have 2 wires of different voltage then at least one of them is a different voltage than ground. If you complete the circuit current will flow regardless of weather a “ground” connection is part of their electricity standard.

      1. [quote]I’m not sure that’s how it works… The ground has a voltage of 0 or “neutral” voltage.[/quote]
        You definately did not understand aztraph’s claim.
        “ground” only has a “0 voltage” if it is connected into the utility grid, usually at a point in the power plants.
        If the “ground” is not connected into the grid, then it’s effectively the same as standing on a rubber mat in a system where “ground” is connected to the “ground wire”.

        I have vague memories this would create problems with capacitive coupling.

    2. No-one uses an earth ground in their electrical grid. Earth ground must be created locally. In the US, earth ground for homes is literally a long copper coated steel rod driven deep in the ground. The neutral line from the step-down transformer (mounted on the telephone pole) is the connected to the local earth connection at the breaker box where the power enters the house (called a bonded ground).

    3. Brazilian power grid has a grounded neutral. It also has a ground wire, that on the non-falsified showers is connected into a grid that the water passes through after it leaves the heating element.

      1. So does Mexico. I showered in a hotel where the naked light bulb above the shower was connected with one wire to the junction box on the wall, the other one with a hose clamp to the pipe just before the shower head! So if there was a break in the plumbing or there were plastic pipes somewhere on the way to the shower and air bubbles in the line, I would become the path for the Neutral return current.

    4. The concept of a ‘neutral’ wire tied to Earth ground came about because insulation isn’t perfect, people run electrical wires in stupid places, and accidents happen. That is to say, a lot of people were electrocuted because one of the mains wires accidentally came into contact with ground, and they completed the path between the other wire and ground. Bonding one wire to ground means that you ALWAYS, (provided it’s wired to code), know which one is dangerous. The ground also provides some protection against extreme voltage surges, i.e ones that cause the striking of arcs, such as those created by nearby lightning strikes. Lightning strikes are, by definition, trying to complete a path to Earth ground. The proximity of a ground wire, (or a grounded junction box or metal appliance housing), helps prevent that surge from using a nearby human as a conductor.

    5. The safety of the ground wire isn’t about it being safer when you touch wires you’re not supposed to touch, it is about the safety when a short happens inside of a device. If any conductive parts in the chassis are connected to a ground wire, then when you smash it with a hammer and the hot wire shorts to the case, it draws full current and throws the breaker. This improves safety, because otherwise the device could be sitting there with the chassis at a high voltage. Also, fire danger is lower if you short out completely and throw a breaker or burn a fuse than if you’re shorting out part way for a long time.

      It is like the device is sitting there on a rubber mat, and you don’t know anything is wrong, and then you touch it and provide a path to ground!

      If your power comes in over jumper cables with no breaker box, you definitely don’t benefit from ground wires, though!

      But also, don’t think it means there is no connection anywhere between neutral and earth, because often there is! Maybe your neighbor tied theirs to the water pipes to improve TV reception.

    1. If the green wire had a lot more bare surface area and the connection wire was a lot longer to you could make the connection two meters away from the shower, it could even be quite safe. for a while.

    1. As usual, people end up lumping all of a continent as the same thing.

      Around work, many people here have the same height ( 1.7 to 1.8 meters ) . So if tourists are to be much higher, where are these 2.5m tourists coming from ? Mars ?

      Those kind of shower heads ( the only place where I have seen they called suicide showers is in hackaday articles ) are used here from almost a century. And the most tales of incidents I remember hearing are from people that use gas heaters.

      If installed correctly ( ground wire, correct sized wire, etc ) they work ok and are perfectly safe. If people use the wrong parts ( some auto-called electricians like 220V instalations because they can use thinner wire, so we can see where those leads … ) then problems obviously will occur. What would happen if someone uses garden hose in the installation of a gas heater just to save costs ? Or cheap pvc tubes intended only for electrical wiring in a pressurized water system ? Also , the codes suggest soldered splices, or ceramic screw blocks. People that just twist the wires together cannot expect much quality :)

      I cannot say for the other countries, but for probably more than half a century the electrical codes here in Brazil specify ground wires in all the instalations. If people install them or not is not a fault of the code or the manufacturer of appliances. Again , some bad installers just connect the wire to anyplace, some even to the steel armature of the walls in a building.

      1. if none of the 2/4 wires coming into the house aren’t grounded locally, the GFCI might not work because the resistance to the next grounding place is “to far away” and thus the ground fault current might be to low….

        1. The ground point is specified to be at the meter, at the entrance to the house. About 3m long copper bar dug into the ground. Length changes depending on soil wetness and size of installation.

  6. Showerhead heaters were pretty common in poor and not-so-poor areas of Costa Rica when I was there 10+ years ago. I saw (and used) some terrifying installations. Like the one wired to an exposed knife switch on the wall. And none of these places had a third wire to attach the ground wire to, but one genius made up for it by taping the ground to the water pipe.

  7. Regarding the material of heater … I strongly suspect it’s not Nichrome. (I once tried using Nichrome as an immersion heater. It worked for a while, then stopped, and the water had turned green with what I assume was some oxide of chromium.)

    I’d guess it’s just stainless steel. 316 Stainless has a resistivity of 7.5e-7 Ω·m, so 1 meter of 28 ga stainless has a resistance of 9 ohms.

    1. it is nichrome you just need to know the variances on the alloy (80, 60, other), diameter of the wire (for this application from 18 to 22), distance from point to point (inches, centimeters), turns in that distance (usually 12 for warm and 36 for hot), diameter of coil (from 1/4 to 1/2 inches), basically, then install it and the most important thing… whenever the wire gets red it has to have water around otherwise it will burn and split.

    1. This is truly one of the most horrific thinks I’ve ever heard. The fact this is tripping the GFI means it will eventually kill someone when the ground wire oxidizes before you replace it. I am starting to look at Brazil as a very primitive society to allow this technology.

      There are real in-line CSA/UL/CE compliant ceramic water-heaters people often use for RVs… that even run on batteries, and last a very long time (5 year guarantee). For the love of electric Jesus, please start making or selling them in your town.

      Whoever made these shower heads are murderers.

      1. I do not really know how these showers work in order to not kill people, but I assure you they don’t.

        Regarding your comment about normalization and safety in Brazil, I would like to point that the country is strictly in line with the best practices and international normalization; this is due to the markets we export goods to (EU, US, etc) require us to comply withe their sh*t (CSA/UL/CE), so basically whatever we sell to you we consume internally too.

        As per ceramic heaters used in trailers, I do not know why it is not adopted massively (since you pointed out it is much safer that the current solution used in here).

        1. I know that very similar high power instant water heaters (up to something like 24kW) here in Europe are also available, they are also called “blankdraht” (bare wire) heaters. they are 3 phase with the star point to the outlet side and have a specification for maximum conductivity of the water. They are installed more centrally than a shower head but the rely on the not-so-good conductivity of normal water and some length of the water column. Together with grounded pipe work the work without any problems.

      2. 48,830 total gun deaths in USA in 2021; overall statistics for road deaths, cardiac problems from obesity etc etc were more difficult to find but I suspect that there are lots of things that you should want banned in the USA.

    2. Lots of things people do can be leading causes of death in an area without generating discussion. What you hear about has more to do with what the local news wants to talk about than anything else.

      I’d want to know that some actuarial accountants had spent a bunch of time on it and produced some numbers before I’d believe even that the number of deaths was low rather than high! If people never talk about it, there are lots of potential reasons, including that the cause of death might get attributed to something else.

  8. This kind of appliances can be enhanced:

    -Using solid state on/off control(now really cheap).
    -electric isolant covered heating element.
    -connection terminals far from water.
    -Making this heater a pass element quite far from shower.

    1. What would hat do? Simple mechanical systems are generally more reliable than similarly priced electronic control systems. Look at a microwave, the device that turns the tube on and off is a relay and not a tirac.

      Isolating the element would cause it to be a bit less efficient I think, and I am not sure of the gain.

      The connection terminals away from the water, I would go along with that, but if you have ever worked on a submersible water pump they do make connections that are water tight.

      The heater, I would consider to be more of a booster. To be able to take tepid water and make it hotish. As previously stated it does not have near the power to make cold water hot. Moving it further away from the showerhead just reduces it’s effectiveness even more.

      I am not sure I am ready to try one yet, but if they work for a large portion of the world they can not be killing everybody off. It would be interesting to see when there is a fatality what causes it. As it was shown it rattled my western sensibilities but at the same time if all I saw were his meter readings of the unit when it was grounded, I would be hard pressed to say it seems dangerous from that.

      I look at it kind of like the electric equal of a gasoline powered self pressurizing camp stove. If you have never seen one of these it is a small metal gas tank that has a pipe at the top that is connected to the burner you cook over. The gas tank also sits over part of the burner. You fill the tank, put the cap on, tip it so a bit of liquid gas dribbles into the burner and light it. You get a big poof of nasty orange flames that slowly die down and if all goes well that is enough to heat the gas in the tank and over a few minutes that starts to vaporize and your nasty orange flame slowly turns into a nice hissing blue flame, just like on a gas stove. They work, but you are cooking on a minimally controlled molotov cocktail. These too rattled my western sensibilities at first but I soon get used to them and they start to seem normal and safe if used correctly.

      In my very own shop I frighten people. I have a vent free propane heater in one of the normally unheated shops. I run it off a 20 pound tank. The 20 pound tanks don’t have a lot of surface area for the gas to boil out of the liquid, even less gas boils off when it is really cold out. So, what do I do? I keep the tank on top of the heater. Freaks people right out. But over the course of a day the tank barely gets warm to the touch and I can not see a difference between the “Hi” and “Low” setting for the burner so I suspect it is still not getting as much pressure as it really wants, but much like the camp stove, it definitely burns better once it has warmed up, and I am not the slightest bit paranoid of the tank exploding. It stands a much better chance of doing that on a hot summer day.

  9. Never heard of anyone dying while using an electric shower head.

    Some better houses around here will have solar heating for water. You can then use the electric shower when cold and leave it off when you have hot water from solar heating.

    In the end, it’s just a lot of whining from people who never used one or know how it works. Yeah, there are Darwin award installations, but this happens for a lot of different things everywhere in the world.

  10. In a rich vs poor societies I would like a head count of deaths by “electric shower heads” versus firearms deaths (hello USA) or car accident deaths … or drug related death.
    Zero to ? ? ?

    1. Actually if you consider death by firearms Brazil wins easily, the same in car related accidents and I am quite sure Brazil would make a number near America in deaths by drug related incidents too.
      I live in Brazil, I have a degree, studied and worked in US and Singapore, can speak four languages, drive a BMW M5 and no, do not have a “Suicide Shower” in my home.
      Actually, I never seen anyone here in Brazil using this term : “Suicide Shower” this is something new for me(and I am almost 50 yrs old) altought I remember to enjoy hot water from these things as a boy many times. As a grown up I even changed the heating elements, and sometimes patched them.
      As an electrical engineer I seen many poor places in Brazil, some of them had no electicity, but they could use many innovative tricks to have hot water. I do not know if you guys are aware but south Brazil can be cold in winter, also the biggest brazilian city (São Paulo, Southwest Brazil) can alternate between 5 degrees in the winter to 40 in summer.
      But the point is : Brazil is a place of many extremes, we can have very rich people, and very big cities, also we can have very poor places too. Brazil is not for beginners: life here can be hard. People have to struggle to have their stuff the same as in US. But one can live confortably here too. I think LH could have an entire series about “Brazilian hacks” if they had a writer able to read portuguese. I could tell a dozen stories about living off the grid in Brazil, here the term “Necessity is the mother of invenction” have been around for more than a century….

  11. I’ve had to use a 120v version of one of these before. It didn’t heat the water up so much, just took the edge off the frostiness of it. It only shocks the hell out of you if your toe touches the metal shower drain…

  12. https://www.vaillant.de/downloads-1/prospekte-2/prospekt-elektro-warmwasser-stand-02-17-939731.pdf
    European VDE-approved instant heaters actually exists. They aren’t like showerheads but like tiny boxes that could be wall-mounted and could have an integrated facet. I’ve actually used one in a lodge and worked (sort of: instead of water at 1 C you’ll get water at 30 C with some patience) Anyway they’re more costrly, almost the price of a regular electric boiler.
    Anyway is possible that an up to code showe head is mada but is more costly? The one on the video has a lot of ut corners to make it cheap. I suppose that a sealed resistance in a grounded tube, plated contact on the switch, sealed switch and sealed connector for the mains wire will make the head up to code but a lot more costly.

  13. Scary though good wiring and a GFI breaker would greatly reduce the danger.
    I’m surprised solar hotwater heaters have not caught on more in Brazil as they would work very well there though the up front cost and need for an separate pipes for hot water might be one reason.

  14. With such a device at hand you may as well cook up some eggs on a portable burner along with toasting your morning bagel all from the comfort of your bathtub while at the same time balancing a 15 inch CRT television on your knee. What could go wrong?

    1. Hmm, is this prescience since you are 44 and maybe close to end of life when you say “until today” – oops :D
      Your name link goes to “The link you followed may have expired, or the Page may only be visible to an audience that you aren’t in”

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