My friend Mike texted me: “My wife doesn’t understand thermostats. Maybe my biggest pet peeve.”

This got me thinking about how the design decisions of one interface can completely throw off the intuitiveness of other interfaces.

Home thermostats start with a pretty big intuitiveness problem: When you set them to a temperature, air starts blowing or radiators start radiating at a different temperature than the current air. The perceived and actual temperature of the new air can vary widely.

Because you’ve set the temperature to a specific number immediately prior to the variable-feeling air that comes into the space, it’s totally reasonable to assume that the temperature you’ve set is relevant to the temperature of this new air.

It isn’t.

Allowing for some ramp up/down, HVAC systems are either distributing the hottest or coldest air they can until the temperature reaches the number on the thermostat. Then they stop.

But when it’s “really hot,” a not-small percentage of people set it “really cold” to compensate.

What ultimately ruined people’s understanding of how thermostats work is the car thermostat. Car thermostats have the same controls as a home thermostat, but the blowing air, from inches away, is dialable to the just-right-goldilocks temperature. It’s intuitive. It “makes sense.”

I don’t claim to have the solution to thermostat interface design, but I think it might look a lot more like a progress bar than the current ambient temperature ticking up or down.

70 [🟧🟧🟧——————]

That might help.