I don’t know about anyone else, but I pretty much never use my faucets on the hottest temperature. In fact, I can’t, because it’s really painful and I’m pretty sure can cause actual burns if you hold it for long enough. For bathing and hand washing, I typically turn the faucet to anywhere from the half to two thirds hot point, any more and it’s uncomfortable.

Which got me thinking, why is domestic hot water that hot to begin with? Why are we spending energy to heat it to a point where we can’t comfortably and safely use it without cooling it back down with cold water? Wouldn’t it make more sense to heat it to no more than a comfortable showering temperature, and just use the faucet on full hot water? Not only would we be using less energy in the water heater (and less CO2 emissions if you’re using a gas water heater or an electric water heater with the electricity from a nonrenewable source) less hot water would also lose less heat in the pipes and water heater itself, because the rate of thermal energy loss is directionally proportional to the temperature difference between the hot and cold regions. And water heating is one of the biggest energy consumers in the residential setting, so reducing it would be pretty significant.

And, if the water pressure in your home fluctulates a lot, by avoiding the water mixing step, you avoid the issue of the cold water pressure suddenly dropping and the temperature at the faucet spiking and burning you (I lived in a university dorm with really unstable water pressure, and it was a constant problem). You also avoid that thing where you turn your faucet too far to the hot side because the water in the pipe is cold, and then having to adjust it a hundred times to maintain a comfortable temperature as the cold water in the pipe is flushed out.

Most water heaters let you turn the water temperature down pretty low, so there’s no real technical reason you can’t just have it make “kind of hot but not scorching water”. And in the rare times where you do need really hot water, you can always just boil some on the stove, and still save energy overall because you won’t have to do it very often.

What do you think? Should this be a change worth making? Any drawbacks that I’m not thinking of?

  • @[email protected]
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    182 years ago

    There are sanitary reasons to keep a minimum regular temperature in hot water lines; temperatures below 51°C promote the growth of legionella.

    The German wikipedia has lots of background; to summarize, it’s a game of trade-offs around energy, storage, hygiene and safety.

  • @[email protected]
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    122 years ago

    If you have a gas heater you can lower the temperature. I do that and it saves gas and water in the shower.

  • poVoq
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    102 years ago

    The return of the famous shower topics on Lemmy 🤣

    This reminds me of the early days…

  • @[email protected]
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    62 years ago

    Growing up my parents had the water temperature lowered for safety, as far as I know. You have no chance of burning. This is only possible if you have a large enough tank so you can do stuff like take a shower with hot water only.

    Normally the water is extra hot because you mix it with the cold water and that gives you a larger quantity of water to shower with. Where I live now, the tank is so small that it would run out if you set it at a lower temperature.

    I have also showered with self-boiled water. Also a useful life skill to learn.

    • poVoq
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      42 years ago

      Exactly, such hot water boilers with tanks used to be extremely common and they only work well if the stored water temperature is very high.

      In modern installations this is not necessary anymore and often there is already a mixer to lower the temperature installed at the outlet of the central tank if you have for example a solar water heater.