Wax elements are also used in thermostatic valves for faucets (to keep faucet temperature constant given variable hot and cold mains): https://rogerdickey.com/the-ideal-faucet/
Wax elements are also used in thermostatic valves for faucets (to keep faucet temperature constant given variable hot and cold mains): https://rogerdickey.com/the-ideal-faucet/
Thermostatic mixers make sense for continuous flow applications - showers, filling a large bathtub for example. But I don't think they make sense for a kitchen tap - where you might be filling a small basin.
The goal is that the water in the basin is the correct temperature, not the stream filling it - which means you need to compensate every time based on how much cold is already there before the hot water arrives. And that varies seasonally.
The time it takes for hot water to arrive tends to be a big proportion of the total time the tap is running, so you actually don't want controlled 40C water once hot water arrives. Perhaps if you had instant hot water, this would be useful.
...what is the point of starting this post with an egregious slop image?
Hard disagree with that faucet design, but is a neat idea. I like my bathroom faucet as low maintenance as it already is.
The use case for the full unmixed hot tap is hygiene (usually washing face and shaving).
I also don't want any hot water mixed in when I'm washing my hands. The water coming out of the unmixed cold tap indicates the ambient temperature of the pipes. That's a feature, not a bug.
You should use warm water when you're washing your hands.
Why?
I'm already upset enough about what the water heater water is doing to my skin and am about to go tankless under my bathroom sink!
That's by far the more practical option anyway if we truly cared about the problem instead of fawning over engineer porn. The problem is solved. This is pointless engagement about temperature preference masquerading as something more interesting.
Solubility is a function of temperature.
It used to be public health recommendation (bathrooms in commercial buildings will often only have warm water, for example, because code required it).
There's been studies demonstrating that soap is what matters.
The comment after yours, about solubility, casts serious doubt on those studies. Physics isn't changed by a faucet.
I mean, no it doesn't, first principles aren't worth more than actual outcomes.
Soap and friction do the work. But people are generally willing to wash for a longer period of time if the water temperature is comfortable.
Anyone who has handwashed many dishes could tell you that cold water will work, but hot water works faster and with less effort. It's no different for your hands. For best results use hot water to wash your hands and cold water to rinse them then put some lotion on them if you worry about them drying out.
at least in my home, both the cold and the hot water are very uncomfortable to wash my hands in, but mixing it right takes ~15s every time so i usually just accept the discomfort
there is this thing named "Single Lever Wash Basin Mixer Tap".
I think it takes time because the hot water line doesn’t immediately return hot water
About 3-5 seconds depending on plumbing.
... if you have a recirculator. The farthest faucet from a water heater takes around 60-90 seconds to deliver actually hot water at my house.
Moen figured out a good enough solution without wax called moentrol
Push/pull adjusts volume, rotation adjusts hot/cold mix
It doesn't maintain temperature at all; it maintains the hot/cold mix.
The problem is that the hot temp varies widely (and the cold temp varies slightly as you drain the house tubing reservoir and begin drawing ground-temp water).