5 ms·

Huh? Regular thermostatic valves do not provide perfect regulation but they do in fact provide a fairly stable output temperature regardless of cold and hot wat

Huh? Regular thermostatic valves do not provide perfect regulation but they do in fact provide a fairly stable output temperature regardless of cold and hot water temperature, by entirely mechanical means. I have a cheap IKEA shower control and output temp is stable for the full duration of my shower even though cold nor hot water supply is stable due to a shower drain heat recovery unit. The article is mainly about wanting the regulation to be between 35-45C instead of 15-55C.

achenatx 4y ago
you can change the top end by lowering the temperature of your hot water heater. We have ours set at 120. Using a lower hot water temperature is a way to give you a wider range of useful temperatures. In texas during the summer we often take showers with no hot water (or very little hot water).
- trynewideas 4y ago
  This isn't always feasible depending on the location, age, and type of water heater, and how many things with different temperature needs are connected to the same water heater. A tankless water heater with a feeder pump, dedicated to bathroom use and with a bathroom-installed remote control, makes this trivial. It's probably also more efficient, easier to use, and (vs. thermostatic valves) about as easy and maybe also cheaper to implement than any fussing with valves. A 30-year-old tank heater in a basement that needs a wrench to adjust a temperature that won't meaningfully change in a 2nd-floor bathroom for another half-hour, and also has to serve a dishwasher and clothes washer that might also run at higher temperatures at the same time, can't swing this as easily, or at all.
- Someone 4y ago
  > you can change the top end by lowering the temperature of your hot water heater. We have ours set at 120 I’m not sure that’s a good idea. 120F is in the danger zone for Legionnaires' disease. https://en.wikipedia.org/wiki/Legionnaires%27_disease#Prevention https://en.wikipedia.org/wiki/Legionnaires%27_disease#Preven...: “Keep water temperature either above or below the 20–50 °C (68–122 °F) range in which the Legionella bacterium thrives.”
  - adamj9431 4y ago
    Interesting. On the other hand, when bringing a newborn home from the hospital, the take-home literature instructs new parents to turn the water heater down to 120 F to prevent risk of scalding.
    - stdbrouw 4y ago
      I wouldn't worry about it. Almost every modern boiler will bump up the temperature to 60C / 140F once a week to prevent Legionnaire's, may even be a mandatory feature depending on where you live.
  - exmadscientist 4y ago
    The "right" way to do this is a thermostatic mixing valve at the water heater output. This lets you keep the tank at 150°F (or whatever) but the output gets mixed down to 120°F (or whatever). It also gives you an effectively-larger tank which can be very useful in certain cases. Of course, you might say, why not put the thermostatic mixing valve at or in the shower, which also works pretty well!
  - kps 4y ago
    > the 20–50 °C (68–122 °F) range That's clearly a case of conversion results being given unwarranted precision.
Kim_Bruning 4y ago
Are cheap thermostatic shower mixer controls not so common outside middle-of-europe? This is the one with one grip that lets you set the temperature, and the other sets the flow rate. It'll (try to) hold the output temperature steady even if the input temperature varies a bit.
- nicd 4y ago
  In my experience (US), they seem to be uncommon in residential properties. I've seen them in many hotels, though.
- nemetroid 4y ago
  Indeed this solution has been standard in much of Europe for decades. It seems to have had slower uptake in the US. Donald Norman’s ”The Design of Everyday Things”, 2013 edition, contains this passage in a list of different faucet designs (p. 151): > Control temperature and rate of flow. Use two separate controls, one for water temperature, the other for flow rate. (I have never encountered this solution.) I e-mailed Don about it a few years ago, and by then he had encountered it.
  - midoridensha 4y ago
    I guess this Don person never traveled outside North America.
- midoridensha 4y ago
  We have the same thing in Japan; they look almost identical to the controls I've seen in Germany. I just leave the temperature control set to the same position, and turn the other side to get the flow rate I want. It's amazing that Americans don't even know these things exist, and are still using ancient pressure controls instead.

achenatx 4y ago

you can change the top end by lowering the temperature of your hot water heater. We have ours set at 120. Using a lower hot water temperature is a way to give you a wider range of useful temperatures. In texas during the summer we often take showers with no hot water (or very little hot water).

trynewideas 4y ago
This isn't always feasible depending on the location, age, and type of water heater, and how many things with different temperature needs are connected to the same water heater. A tankless water heater with a feeder pump, dedicated to bathroom use and with a bathroom-installed remote control, makes this trivial. It's probably also more efficient, easier to use, and (vs. thermostatic valves) about as easy and maybe also cheaper to implement than any fussing with valves. A 30-year-old tank heater in a basement that needs a wrench to adjust a temperature that won't meaningfully change in a 2nd-floor bathroom for another half-hour, and also has to serve a dishwasher and clothes washer that might also run at higher temperatures at the same time, can't swing this as easily, or at all.
Someone 4y ago
> you can change the top end by lowering the temperature of your hot water heater. We have ours set at 120 I’m not sure that’s a good idea. 120F is in the danger zone for Legionnaires' disease. https://en.wikipedia.org/wiki/Legionnaires%27_disease#Prevention https://en.wikipedia.org/wiki/Legionnaires%27_disease#Preven...: “Keep water temperature either above or below the 20–50 °C (68–122 °F) range in which the Legionella bacterium thrives.”
- adamj9431 4y ago
  Interesting. On the other hand, when bringing a newborn home from the hospital, the take-home literature instructs new parents to turn the water heater down to 120 F to prevent risk of scalding.
  - stdbrouw 4y ago
    I wouldn't worry about it. Almost every modern boiler will bump up the temperature to 60C / 140F once a week to prevent Legionnaire's, may even be a mandatory feature depending on where you live.
- exmadscientist 4y ago
  The "right" way to do this is a thermostatic mixing valve at the water heater output. This lets you keep the tank at 150°F (or whatever) but the output gets mixed down to 120°F (or whatever). It also gives you an effectively-larger tank which can be very useful in certain cases. Of course, you might say, why not put the thermostatic mixing valve at or in the shower, which also works pretty well!
- kps 4y ago
  > the 20–50 °C (68–122 °F) range That's clearly a case of conversion results being given unwarranted precision.

Kim_Bruning 4y ago

Are cheap thermostatic shower mixer controls not so common outside middle-of-europe? This is the one with one grip that lets you set the temperature, and the other sets the flow rate. It'll (try to) hold the output temperature steady even if the input temperature varies a bit.

nicd 4y ago
In my experience (US), they seem to be uncommon in residential properties. I've seen them in many hotels, though.
nemetroid 4y ago
Indeed this solution has been standard in much of Europe for decades. It seems to have had slower uptake in the US. Donald Norman’s ”The Design of Everyday Things”, 2013 edition, contains this passage in a list of different faucet designs (p. 151): > Control temperature and rate of flow. Use two separate controls, one for water temperature, the other for flow rate. (I have never encountered this solution.) I e-mailed Don about it a few years ago, and by then he had encountered it.
- midoridensha 4y ago
  I guess this Don person never traveled outside North America.
midoridensha 4y ago
We have the same thing in Japan; they look almost identical to the controls I've seen in Germany. I just leave the temperature control set to the same position, and turn the other side to get the flow rate I want. It's amazing that Americans don't even know these things exist, and are still using ancient pressure controls instead.