HVAC Residential Service: Serving Prince Frederick South in Calvert County and All of St Marys County in Southern MD

Heat Pumps, Heating & Cooling System Installation Services & System Types

  • Propane Furnace Installations
  • Propane Furnace Service & Repair
  • Radiant Heating Installations
  • Radiant Heating Service & Repair
  • Heat Pumps Installations
  • Heat Pump Service & Repair
  • Air Conditioning Installations
  • Air Conditioning System Service & Repair
  • Heating & Cooling Zoning
  • Heating & Cooling System Service Agreements
  • Heating & Cooling System Service & Repair
  • Heating & Cooling Air Duct Cleaning
  • Direct Heating & Cooling System Replacement
  • Heating & Cooling System Service & Repair
  • Oil Tank Installations
  • Oil Tank Service & Repair
  • Oil Furnaces Installations
  • Oil Furnace Service & Repair
  • Gas Furnaces Installations
  • Gas Furnace Service & Repair


We service or repair the following heating and air conditioning manufacturers. In addition, we can replace the following heating and air conditioning manufacturers with Carrier.

Airquest, Airtemp, Amana, American-Standard, Armstrong, Bard, Bryant, Carrier, Coleman, Comfortmaker, Crane, Daikin Us, Ducane, Fasco, Fraser-Johnston, Fedders, Friedrich, General Electric, Green, Colonial, International Oil Burner, Intertherm, Iron Fireman, ITT, Janitrol, Johnson Air-Ease, Lennox, Luxaire, Magic Chef, Mayflower, Mcquay, Miller, Climatrol, Payne, Peerless, Rheem, Ruud, Square D, Tappan, Trane, Westinghouse, Whirlpool, Williamson, York.

Financing Options

Great Mills Heating and Air offers various financing options:

Click the image below to apply for Wells Fargo Financing.
Wells Fargo Financial

Call the office for other options 301-994-0522.


Call Us or Email Us

for Info on SMECO Rebates and Carrier Spring Rebates On complete HVAC system installations!

Call UsCarrier logoPuron logoNorth-American-Tech logoall credit cards accepted