Chief Investigative Correspondent Lisa Guerrero and the Inside Edition I-Squad put air duct service people to the test in the fourth installment in a special series of investigations. Inside Edition rented a house in Montclair, New Jersey, for an entire month, tricking it out with more than a dozen hidden cameras and then calling in the fix-it guys to see what would happen. For the fourth installment, we enlisted air duct-cleaning experts from the National Air Duct Cleaners Association, Mark Zarzeczny and Anthony Paterno, who have a combined 50 years of experience, to fully inspect the home's air ducts. Then, we called in the technicians. #InsideEdition