If you are replacing a thermostat, check to see if the old thermostat has a mercury switch. Remove the cover and look for a glass capsule with a silver liquid. Mercury is dangerous and toxic and needs to be recycled. You can go to thermostat-recycle.org or earth911.com and enter your zip code for a local recycler. If you have a mercury spill call Poison Control at 1-800-222-1222. You can call your local village or go to the EPA website for tips.
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