The EPA-certified techs at D's Air & Heating install furnaces, boilers, and air conditioners. Beyond installation, the HVAC experts can tune up homes' water and air systems, and they specialize in mold inspection. Because indoor air is recycled, mold can sometimes spread quickly and easily. As it grows, it may cause nausea, allergic reactions, and can even suppress immune systems—not to mention wreak severe damage to homes. D's specially trained techs start the inspection process by examining HVAC systems for signs of mold and moisture. They then collect samples, sending them to the lab where the mold can be analyzed through a battery of tests and questions about its childhood. Once the variety has been identified homeowners will have a better idea of how to deal with the situation.