Submitted by MSica on Wed, 12/14/2022 - 10:03 Switching to a Smart Thermostat? Some older thermostats contain a small amount of mercury. When you upgrade, recycle your old thermostat for safe disposal to prevent the release of its mercury into the environment. Collection facilities like the Thermostat Recycling Corporation will recycle it for you at no cost! Find a thermostat collection site.