First Class Heating, A/C & Plumbing Inc. PlumbersHeating & Air First Class Heating, A/C & Plumbing Inc. Visit Website Request Info 28418 DuPont Blvd. Millsboro, DE 19966 (302) 934-8900 (302) 933-0334 (fax) About Map About HVAC, Plumbing, Duct Cleaning, Geothermal What's Nearby? Distance: 5 10 15 20 25 50 mi.