If it seems like changing your hotel thermostat isn't working, that's because it's not.
The Wall Street Journal reports many of the thermostats have an override to maintain control.
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While some savvy travelers have figured out how to 'override the override' - newer devices can reportedly block those too.
For many hotels these thermostats have been given a major energy-saving upgrade and can detect heat and motion, adjusting up or down if someone opens a window or exits the room.
Letting guests crank up the air conditioning can also require additional maintenance costs so the systems are meant to make guests more comfortable while decreasing costs.
However, they're not exactly foolproof, the WSJ suggests the thermostats can by off by as much as 20 percent due to poor maintenance.
But some guests have figured out how to trick the sensors with something as simple as an arm wave.