Thermostats Alternative ways to recycle Illegal in Garbage & Drains Contains Mercury Special Instructions See Item info below. How to Check for Mercury Remove the thermostat’s cover and check if you see a bulb or vial that contains a silver, metallic liquid. If present, this liquid is mercury. Do Not Throw in the Garbage A thermostat that contains mercury should be disposed of as hazardous waste, so never throw them in the garbage. Smart and Digital Thermostats Are E-Waste Smart thermostats and digital thermostats need to be disposed of as e-waste. Alternative Ways to Recycle Return to an HVAC Wholesaler Heating Ventilation and Air Conditioning (HVAC) wholesalers are required by law to accept mercury thermostats free of charge. Find collectors who will recycle your thermostat. Ways to Reduce Replace Mercury Thermostats Most thermostats are made without mercury now so they are less damaging to the environment and more energy efficient. Consider updating your thermostat to save energy, money and avoid a hazardous mercury spill.