These little control modules play a crucial role in ensuring that HVAC equipment performs at its best.
(NOT SO) SMARTProgrammable thermostats automatically turn the temperature up or down at preset times. Setbacks of 10 degrees for 8 hours can achieve savings of up to 10 percent. Good for households with predictable schedules, but many people don’t bother programming them anyway.Shown: Focuspro 6000, $49
SMARTThanks to occupancy sensors and geofencing features that detect our comings and goings, these devices reset temperatures automatically, saving up to 15 percent when cooling. They’re smartphone enabled, so you can monitor and adjust them remotely.Shown: Nest 3rd generation, $249
ULTRASMARTThey have many of the features of a smart thermostat, but these proprietary devices also communicate with a company’s equipment to maximize humidity removal, air quality, and system efficiency, tasks that run-of-the-mill smart ’stats can’t handle.Shown: iComfort S30, starting at $450
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