37 Maintenance and repair of heating and air conditioning systems, namely, duct cleaning, pipe cleaning, drain cleaning, pipe unclogging, sewer unclogging, leak repair, fixture repair; maintenance and repair of electric and gas appliances, namely, furnaces, boilers, air conditioners, gas fireplaces, air cleaners, humidifiers, dehumidifiers, water heaters, ranges, ovens, microwave ovens, grills, fans, refrigerators, freezers, dishwashers, garbage disposals, washers, dryers, space heaters; [ installation, maintenance and repair of home security and safety equipment, namely, intrusion and burglar alarms systems, security panel, sirens, motion sensors, motion sensitive lights, smoke, heat and fire detectors, carbon monoxide detectors, natural gas detectors, moisture level sensors, temperature level monitoring sensors, glass breakage sensors, door sensors, and alarm point monitoring software ]