The ones I’m talking about doesn’t just keep the pressure ratio static, they actually adapt to the temperature of the hot and cold water.
If the hot water drops in temperature, then the output water stays at the right temperature, but the output pressure might drop, as the mixer allow more of the hot water through, and less of the cold water.
Of course if the hot water drops below the set temperature, it can no longer maintain it’s temperature.
And yes these are also entirely mechanical, no electronics or even electricity.
There’s not much reason for that to happen unless the building’s water heater has failed or is undersized. I have had that happen once in the decades I’ve lived at this house and it was a simple matter of turning the handle up a bit hotter.
Otherwise, the effect thing you described (the mixer lowering the pressure to maintain a constant output temperature, assuming the hot water supply is constant temperature) works just fine. I have never had the water suddenly become unexpectedly hot or cold after the initial warmup phase.
The ones I’m talking about doesn’t just keep the pressure ratio static, they actually adapt to the temperature of the hot and cold water.
If the hot water drops in temperature, then the output water stays at the right temperature, but the output pressure might drop, as the mixer allow more of the hot water through, and less of the cold water.
Of course if the hot water drops below the set temperature, it can no longer maintain it’s temperature.
And yes these are also entirely mechanical, no electronics or even electricity.
There’s not much reason for that to happen unless the building’s water heater has failed or is undersized. I have had that happen once in the decades I’ve lived at this house and it was a simple matter of turning the handle up a bit hotter.
Otherwise, the effect thing you described (the mixer lowering the pressure to maintain a constant output temperature, assuming the hot water supply is constant temperature) works just fine. I have never had the water suddenly become unexpectedly hot or cold after the initial warmup phase.