These are two separate things: thermostat will close and open based on surrounding temp., the actuator on the other hand opens and closes based on energizing a heating element that is driven by a separate thermostat.
Wax motors are pretty cool things. They rarely fail and do their job even in damp environments. I take care of my better half's hotel with approx 100 of these installed and we replace one of these once every couple of years.
Wouldn't the thermostatic radiator valves contain a wax motor? According to the definition in the article, using ambient heat as the energy source counts. Or are you saying it's only a wax motor if there's electric heating?
It was so refreshing to see a video with a clear and direct title. In 2026 this would have been "We cracked open a motor. You won't believe what we found inside! <emoji>". Checking the channel, it seems they have succumbed to this for their latest videos.
The expansion of paraffin wax is substantial. I have experience wax potting guitar pickups as well as bicycle chains. I use a skinny, tall tin can for this, placed in boiling water. When the liquid wax solidifies, it not only pulls away from the sides of the can so that the resulting ingot slides out freely, but a void forms in the center. The top surface has a depression and a deep hole in the center.
I'm surprised this page doesn't mention the automotive thermostat which uses the same principle to control the flow of coolant between the engine block and radiator in an ICE vehicle.
The "See Also" has "Wax thermostatic element" [0] which seems focused on automotive applications, so perhaps it was there and grew large-enough that it got split off.
> Its principal application is in automotive thermostats used in the engine cooling system.
What a treasure Big Clive is. Educational, entertaining, and zero of those YouTube cliches and clickbait that everyone hates. I don't think he's ever said "Like and subscribe" literally ever.
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/
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.
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.
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
Objects like this make me think of grimdark (steam|diesel)punk works like the video games Dishonored or BioShock. It feels like there's a touch of occultism or corruption whenever one creates a device that exploits analog side effects to create machines in a closed, black-box package.
I see what you mean, but it’s less the exploitation itself than its immediacy and legibility. It doesn’t vanish behind a million abstractions or complicated miniaturization processes but can be readily experienced and understood, like steam.
On the other hand one might as well associate it with “solar punk”, especially when powered by ambient temperature.
Yes, it seems generally *punk. It’s funny that steam, diesel, and solar punk have this association with immediacy.
Does the originator, cyberpunk? Lots of cyberpunk stories present us with a society that is dominated by a digital abstraction. But the protagonist is special, so, they might not be.
> Objects like this make me think of grimdark (steam|diesel)punk works like the video games Dishonored or BioShock. It feels like there's a touch of occultism or corruption whenever one creates a device that exploits analog side effects to create machines in a closed, black-box package.
The second sentence also fits for field effect transistors and solid state electronics in general.
In the spirit of grimdark steampunk, have you ever heard of pneumatic logic? I still see these systems operating normally in some older mechanical rooms, it’s cool to see them still working after 40-50 years.
I once had an interview at PA consulting where they asked one of those questions where they have "the answer" but their question isn't well specified enough to lead to that unique answer. They kept adding conditions, but I hadn't ever heard of wax actuators before. (I was like 19 or something - didn't get that job!)
It's a simple mechanism that used buoyancy to either open or close valves as water level changes in a container.
https://en.wikipedia.org/wiki/Ballcock
These are two separate things: thermostat will close and open based on surrounding temp., the actuator on the other hand opens and closes based on energizing a heating element that is driven by a separate thermostat.
Wax motors are pretty cool things. They rarely fail and do their job even in damp environments. I take care of my better half's hotel with approx 100 of these installed and we replace one of these once every couple of years.
https://en.wikipedia.org/wiki/Wax_thermostatic_element
> Its principal application is in automotive thermostats used in the engine cooling system.
[0] https://en.wikipedia.org/wiki/Wax_thermostatic_element
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.
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.
There's been studies demonstrating that soap is what matters.
On the other hand one might as well associate it with “solar punk”, especially when powered by ambient temperature.
Does the originator, cyberpunk? Lots of cyberpunk stories present us with a society that is dominated by a digital abstraction. But the protagonist is special, so, they might not be.
The second sentence also fits for field effect transistors and solid state electronics in general.
In the spirit of grimdark steampunk, have you ever heard of pneumatic logic? I still see these systems operating normally in some older mechanical rooms, it’s cool to see them still working after 40-50 years.
https://en.wikipedia.org/wiki/Pneumatic_circuit
TWO HUNDRED SEVENTY FIVE years ago
in 1752, wow
(but they had no idea why it worked)
* https://en.wikipedia.org/wiki/Franklin_bells
Before the storm, the device would ring to remind Franklin, who had been obsessed with the study of lightning, urging him to chase the lightning
ha "chase the lightning" needs to be a catchphrase