The problem: if you're showering, and someone turns on a sink or flushes a toilet anywhere in the house, your water temperature changes, suddenly and without warning. (It's worse if they try an ultrafast, good-intentioned jerk of the faucet handle, resulting in a 2-second burst of icy/scalding water.)
The solution: get a better water system.
The solution for the perpetually broke: The Advance Warning Shower Head. Instead of water coming straight out of the wall and out of the head, the spray nozzle thingy is on the end of 15 or 20 feet of flexible plastic tubing (mountable on the shower/bath wall in cool patterns via suction cup) made of (or interwoven with) material that changes color with temperature (the newest material changes color almost instantly, I think). The water is coming out at a fair speed, so there will be only a very short warning between it exiting the wall and it splashing into the room, but a half-second's notice, delivered in the form of your feild of vision turning red, should be enough for you to step neatly out of the way, or at least cringe before being burnt.-- Tlogmer, Aug 25 2002 Anti-scald info http://www.plumbingsupply.com/scald.html"Most U.S. states now mandate some form of anti-scald measures in building codes." [half, Aug 25 2002, last modified Oct 04 2004] I think this is a cool idea, having been in situations like this. (I know nothing about this technology though.) However the perpetually broke, or those who act like they are and then lease the place to you, are not usually wont to use fancy temperature sensors and the like. Sigh. However that does not invalidate your croissant.-- polartomato, Aug 25 2002 a) Half-Baked - this has been suggested here before, at least twice. b) Baked - the pressure drops on my shower a few seconds in advance of the temperature change, enough warning to dodge out of the way. (If you like, I can sell it to you.) c) Your mechanism is not feasible: those temperature senstitive plastics take too long to change color to be useful. d) If you're perpetually strapped, you won't be able to afford this anyway. e) If you come into some money, buy a constant temperature shower unit.-- DrCurry, Aug 25 2002 Just have a temperature sensor with a valve that shuts the water off instantly if the water is too hot/cold and drain the waste water or pump it back into the system.
Or an even more active system that would, in the event of scalding water detected in the "buffer", would reduce the flow of hot water and add cold water to compensate, creating the perfect water flow system. I can imagine having a PC in my bathroom working full time to compute the ratios of hot and cold water to create the perfect, balanced shower.
A hot-water emergency shut-off may have use in nursing homes and hospitals to prevent the elderly and handicapped from burning themselves in the shower.-- BinaryCookies, Aug 25 2002 While recently on the hunt for a new shower control, I found that about 90% of the units available contained "anti-scald" technology. Seems like the lawyers must have been at work in the plumbing industry. No word on "anti-freeze" shower technology.-- half, Aug 25 2002 I dislike those anti-scald controls because they don't let you set the volume of water that they deliver to the shower head.
How about a rapid reacting temperature transducer located in the hot water supply line a few quarts/liters "ahead" of the shower head? A small warning beep goes off if the temp falls or rises beyond a given threshold.-- bristolz, Aug 25 2002 //because they don't let you set the volume of water that they deliver // is *precisely* why I kept searching until I found the one model that didn't have anti-scald technology. I'd estimate that there were 30+ different models, 2 of which didn't have it.-- half, Aug 26 2002 random, halfbakery