Sensors Containing Mercury

Mercury-containing sensors may be found in some gas-fired appliances that have pilot lights. These include stoves, ovens, water heaters, clothes dryers, furnaces and space heaters. A sensor has a probe that consists of a metal bulb and thin tube attached to a gas-control valve. Mercury inside the tube expands or contracts to open and shut the valve.

Although there are some gas appliances that have been made with nonmercury thermostat probes, you should treat all of them as if they contain mercury. When you replace an old appliance, arrange for the pilot light sensor to be recycled.

Mercury Gauges Disposal Guidelines

Identify gas appliances which are likely to contain mercury.
  • Use stickers or some other form of identification to mark stoves, ovens, water heaters, clothes dryers, furnaces and space heaters that have pilot lights. 
  • Contact IDEM for free mercury stickers:
Properly dispose pilot light sensors - recycle them!
  • When a gas appliance is no longer useful, make sure the pilot light sensor gets recycled. Ask your scrap dealer or appliance recycling center if they professionally remove and recycle pilot light sensors.
  • If they do not have a system in place, take the container to a local mercury recycling site, such as your local solid waste management district, or in Marion County, contact the ToxDrop at (317) 327-2234.
Before you buy, check what's inside.