St. Marys and Calvert County Maryland HVAC Services   ♦   We Make Your Air Flow!

Calvert County Heat Pumps, Heating & Cooling System Installation & Service Repair

Great Mills Heating & Air Conditioning Contractors Inc is a locally owned and operated full service residential, business and commercial heating and air conditioning contractor. They have been repairing, servicing, and installing heating and air hvac units in Southern Maryland and Southern Calvert County (Prince Frederick South) since 1972. Great Mills specializes in the repair, maintenance and replacement of existing residential and commercial comfort control systems as well as oil tank installations, oil furnaces, gas furnaces, propane furnaces and radiant heating.

Some of our many Calvert HVAC services include heating repair in Calvert Maryland, furnace repair in Calvert Maryland, oil furnace repair in Calvert Maryland, gas furnace repair Calvert Maryland. We are a heating contractor in Calvert Maryland, oil furnace contractor in Calvert Maryland and gas furnace contractor in Calvert MD.

Services and System Types: Calvert County MD HVAC

  • Prince Frederick Direct Heating & Cooling System Replacement
  • Calvert County Heating & Cooling System Service & Repair
  • St Leonard Oil Tank Installations
  • Dowell Oil Tank Service & Repair
  • Solomons Oil Furnaces
  • Prince Frederick Oil furnace Service & Repair
  • Lusby Gas Furnaces
  • Broomes Island Gas Furnace Service & Repair
  • Barstow Propane Furnaces
  • Prince Frederick Propane Furnace Service & Repair

  • St. Leonard Radiant Heating
  • Solomons Radiant Heating Service & Repair
  • Lusby Heat Pumps
  • Calvert County Heat Pump Service & Repair
  • St Leonard Air Conditioning
  • Lusby Air Conditioning System Service & Repair
  • Solomons Heating & Cooling Zoning
  • Calvert County Heating & Cooling System Service Agreements
Calvert MD HVAC

Great Mills is your Calvert County heat pump repair, heat pump maintenance and heat pump replacement contractor in existing homes and commercial comfort control systems in the following areas: Lusby, Prince Frederick, St. Leonard, Solomons, and all of Calvert County, Maryland

For a FREE estimate or service appointment click here

Phone: 301-866-1433 Emergency Service after 5pm: 240-925-2230