Maybe electric showers are uncommon in North America for the same reason that electric kettles are relatively rare - lower domestic mains voltage.
This must be different from the device I’m thinking of, then. All through SE Asia (and one cold-water bedsit I once lived in here in Sydney), a lot of places have no hot water in the building, so the shower water is heated by a small electric heater right there at the shower. This means there is only one tap - cold. You then adjust the temperature setting until it’'s comfortably warm coming out the other end. If somebody else turns on a tap in another room, you don’t get burned, you just get a few seconds of lower pressure, but at the same temperature. The ability to scald or freeze a housemate in the shower is usually confined to older houses with “proper” hot water systems (not electric showers), or towns with dodgy mains pressure. I’ve seldom had a problem in Sydney, but in country towns it’s common.
The best thing about those electric showers, is that providing you’re willing to pay the power bills, you can stay in the shower as long as you want.
Do you mean a heating unit local to the tap? If not, where does the cold water in the pipe go when you turn it on?
Yeah, sometimes I forget and have a shower while the washing machine is on a cycle. You can tell when it reaches the rinse cycle.
Basic electric showers aren’t thermostatically controlled. You can switch in 1 or 2 elements and regulate the water flow to some degree, but that’s it. They rely on constant pressure, constant temperature water input to work well.
I once worked on an electronic design for a proper thermostatically controlled instant-water heater, marketed as a cheap hot water source for student rooms and suchlike. Even then you could only use a crude and relatively slow bang-bang servo or it would create illegal amounts of electromagnetic noise from switching the heating element quickly. This element was much smaller than for an electric shower, and properly thermostatically controlling a 10kW shower heating element is too much hassle for a domestic setup. For a shower it’s easier to control the hot/cold input mix ratio to get the desired output temperature.
Maybe one of the reasons the US doesn’t really do electric showers is the puny 110V they mostly have to work with. Sucking a 10kW load off that is going to require some seriously chunky copper cable. Even with the 230V in the UK you need a separate heavy duty shower feed going directly to the electricity junction box, or you’ll eventually blow up every electronic item in the house with the back-EMF spikes from the shower being turned off.
My house was built in 1926. Most of the sinks have been remodeled to have mixer taps, but the half bath on the first floor(which is also colder than hell in the winter) still has a sink with two faucets.
-Lil
There’s one aspect that hasn’t been treated yet: the history of the thing. The chronology of the technology.
We tend to look at things from a modern perspective, and see older things as less than, or not as good as, their modern versions. But you have to see it through the eyes of the people for whom it was a modern marvel, who would of course have been comparing it favorably to what it replaced.
Take talking pictures, frinstance. Most of us today can’t fathom the popularity of silent film and we find it simply hard to believe that many people saw the addition of sound as a BAD thing. At least, it wasn’t accepted with trumpets of joy for bringing movies closer to modern perfection. But the perspective–the paradigm, if I must–was completely different. Today, we see a movie as a simulacrum of real life, and the closer it can come to approximating physical reality–which includes sound, of course–the better we like it.
But in the early days of film, the paradigm was different. The first clue is what they were called: motion pictures. The were pictures. Pictures that moved, but primarily pictures nonetheless. The paradigm was something like, Here we have a photograph, a wonder of modern technology! A photo shows us a likeness unlike any painting has ever done, and it does it quickly and relatively cheaply. And with a technological advance, suddenly that static photograph has come to life, it moves, and it can tell a story!
People didn’t see motion pictures as “reality minus sound,” they saw them as “photographs PLUS movement.” So they were already the result of an improvement; they didn’t necessarily “lack” anything.
The same goes with the double tap. What preceded it? A pitcher full of cold water and a basin. Usually on a wash stand. You want warm water, you boil a kettle and some to the mix. People were used to using a bowl of water to do their washing; hot and cold running water wasn’t part of their paradigm. And then a technological advance comes along and allows us to bring the water–not just the cold water, but the hot water as well–right to the basin, in pipes! Oh joy in the morning!
This was such an improvement upon the previous technology that I doubt anyone felt an immediate need to “fix” it, to bring the water into the basin in a single spout. That’s just crazy talk! My mother mixed her water in the basin, so it’s good enough for me.
It’s only our modern perspective that looks down on separate taps as barbaric. That plus they suck; who wants to mix your water in the damn basin? Then you have to keep it clean.
and
Theoretically maybe. But in reality, these solutions are kludges: desperate attempts to use high technology to get around the basically defective infrastructure, and they tend to fall way short of the mark. For my more colourfully expressed views, see here.
By the way, by “greatest American tradition,” I meant the tradition of demanding everything right now, not to imply that everyone has these water heater pumps.
To answer your question, no, my water heaters are in the garage, and there is a small pump near the bottom of them. This pump makes hot water instantly available from every tap in the house, like I said. I believe the way it works is that there are two pipes going to every sink, shower, and tub - one for the path from the heater to the tap, the other for the return, and hot water is always circulating through my house plumbing.
Seeing how this is a little wasteful, I put a timer on the pump so it operates only during the few hours a day when I actually need it. But it sure is convenient - I can step into the shower and then turn on the water!
Oh my! I had no idea such things even existed. A little wasteful? Yikes. Are these circulatory pipes well-insulated?
Yes, a lot of the old tenement buildings had cold water systems long before a hot water system was fitted along side it - it would have been a lot easier and cheaper to fit a separate tap (just like the cold tap; no new design needed!) and feeder pipes, etc., beside the existing system, rather than rip a lot of piping out and do it all over.
And if that’s how the plumbers were used to doing things, it becomes a normal part of life - two temperatures of water = two taps.
what frequently happened was that the cold feed was branched off into a gas-fired flash heater (known as a ‘geyser’ or an ‘Ascot’, from one of the maker’s names). It saved having to install a whole new hot water plumbing system. My grandparents had one in the kitchen, and a larger one in the bathroom, and used it all their lives [to the end of the '70s]. Never felt a need to upgrade, “it works, why change?”.
My uncle still has a newer version serving the kitchen.
lissener has a very valid point about historical precedent. To that I can add a little history of British bathrooms:
Up until about the 1950s, the average British house didn’t have a bathroom. The toilet was a little shed at the end of the garden, or a chamber pot under the bed if you needed a piss in the middle of a freezing cold winter night. The bath was a free-standing galvanised affair that was ceremoniously dragged out once a week, placed in front of the fire, filled with hot water from big kettles, and bathed in by each member of the household in turn. Only the first person got clean water to sit in! Washing was done in a free-standing china basin in the bedroom, filled with a jug.
If the house had a tap, it would be a single cold water tap in the kitchen, over the only sink in the house. But it was usually a sink big enough to bathe a small child in quite easily.
There was a big housing shortage after WW2, and the Labour government of the time embarked on a big council-house and prefab building spree, and in a truly radical move they were built with inside bathrooms as standard for the first time. This was a luxury for most, and you were very lucky if you got to live in a shiny new house with modern plumbing.
Just want to note that when I lived in Salt Lake (in a 1920’s-era apartment building) I had a bathroom sink with two taps. What’s more, they were spring-type taps, sp that you had to keep the handle twisted if you wanted water to continue coming out. For all the years I lived there, I couldn’t wash both hands at the same time (unless I did it in the bath tub or the kitchen), and I could do it only with ice cold or scalding hot water.
You got used to it.
But I have to admit that the showers in most places I’ve stayed in Ireland or the UK have had maddening water temperature controls. One place in Ireland that three controls that I never did understand – thety weren’t anything easily quantifiable like pressure, temperature, and relative hot/cold, or anything like that. But if you didn’t get them exactly right you’d be scalded or frozen in the shower.
He he he he… British people only like to have a few high quality things? ha ha ha… oh my boyfriend wishes that was true! (actually… so do I after seeing my credit card bill this month… damn you beautiful manolos…so pretty…so expensive… soooo not practical in November!)
In my whole life moving around the UK I’ve always had plenty of wardrobe (closet) space - and I’ve lived in Tudor, Elizabethan/Jacobean, Victorian, Georgian and brand new houses. I agree that there is less often ‘built-in/walk-in’ wardrobes - but stand alone wardrobes are in every bedroom! I am guilty of stuffing things all over my house, but I assure you that is down to lazyness and not lack of storage! Oh - and a gentle thought for you - perhaps not all houses built in 1760 were built the same?!
Nobody picked this up? I’ve learned from the Dope that US has a three-rail system, two of which are ~110V wrt neutral but oppositely-phased - so you get ~220V between the two of them.
Or am I full of it?
This is a pretty fair description; most showers in the UK are electric - that is to say that they work by instantaneously heating the water locally, inside the wall-mounted device - there will usually be a control to adjust the rate of flow and another to adjust the temperature of the heater, but the trouble is that adjusting the rate of flow also affects the temperature (as it has less time to pick up heat if it’s going through faster). Inbuilt thermal sensors are supposed to correct this, but in reality, what they often do is just get into a resonant cycle of overcompensation.
External changes in water pressure (such as someone running a tap elsewhere) will also result in changes to the rate of flow, which means the temperature will abruptly change. In many households, the intention to use the shower must therefore be shouted throughout the house (with the implication that bloody murder will be visited upon anyone daring to flush a toilet or turn on a tap while the shower is in use.
On top of that, because electric showers typically have only a cold water supply and they heat it to order, the maximum flow rate can be rather disappointing to people accustomed to mixer/pumped showers.
So why do we tolerate it? Complex question to which there are many parts of an answer, but I do honestly believe that there’s a difference (becoming less significant over time) in the general attitude and psyche of the British nation
- a perception that, although it would be nice to fix them, certain problems just aren’t big enough to warrant the effort (i.e. OK, electric showers are crap, but how much of our lives do we spend in them?)
- a sense that luxury needs to be rare in order to remain luxurious
You don’t get any thermostatic control in a normal electric shower, just a choice between switching in 1 or both heating elements, and quasi-control over the water flow rate.
There is a thermal switch that sits on the heater can, but it’s just there for safety. It switches out the heater if it goes over-temperature*. If this switch was to kick in at too low a temperature, then you’d get a hot/cold cycling effect such as the one Mangetout mentioned, but that’s not normal.
There’s also a low water-pressure switch that also switches off the heater should the water pressure drop. This is important, because an electric shower heater packs 7 to 10kW in a can the size of a tin of cat food, and if the water were to stop flowing with the heater still on, it would boil in seconds. As an additional safety feature, the heater can will have a pressure relief vent so it doesn’t explode.
These safety features haven’t always been foolproof. I’ve had experience of electric water heaters and showers that have developed a fault where the element remains on when the water flow has stopped, and they make a very scary rumbling noise as they try and boil themselves to death - a bit like a wheelbarrow full of rubble trundling over rough ground, but with an edge of imminent explosion.
*Actually, there’s only one brand of electric shower that switches out both elements in the case of over-temperature condition. They have a patent on the technique, so every other electric shower manufacturer has an over-temperature switch that only switches out one element. A bit dodgy in theory, but seems to work OK in practice.
I was sure I’d seen one with a mechanical thermal flow control valve (coupled to, and adjusted by the temperature control dial) that constricts the flow if the temperature should drop and opens it up when it gets hotter.
It’s possible, and such an arrangement would indeed work in the shit way you describe. Maybe why the technique never caught on.
The problem with this arrangement is the thermal time constant between the water and the thermostat. You can work out the time it takes for heat to travel from the water to the thermostat by measuring the frequency of the hot/cold cycles.
Exactly the problem and any attempt to dampen or introduce hysteresis would just make it unresponsive and useless.