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

Southern MD, St. Marys & Calvert County Commercial Heating & Air Contractor Services


One of our main goals is to give you the flexibility and freedom you need to provide a higher level of comfort in your business environment. Many of Southern Maryland's federal contractors choose us as their primary HVAC contractor. We have also established great working relationships with many of the facilities at Patuxent River Naval Air Station.

Great Mills Heating and Air Conditioning is a local contractor specializing in the repair, maintenance and replacement of existing commercial comfort control systems in the Southern Maryland areas including:

Budds Creek, Mechanicsville, Charlotte Hall, Hughesville, Leonardtown, Lexington Park, Charlotte Hall, California, Mechanicsville, Wildewood, Hughesville, Great Mills, Hollywood, Barstow, Broomes Island, Dowell, Lusby, North Beach, Owings, Port Republic, Prince Frederick, St. Leonard and Solomons Maryland.



We can provide services in the following areas:


  • Commercial rooftop heating and conditioning service or replacements
  • Preventive maintenance on commercial heating and conditioning units
  • Service call on commercial heating and conditioning units
  • Single room temperature issues


Manufacturers we use in our installations and repairs:


  • American Standard
  • Bard Air Conditioning
  • Daikin
  • EWC Controls
Commercial HVAC Southern MD

Give us a call or fill out an online service request so we can make you feel more comfortable today!


Financing Options


Great Mills Heating and Air offers various financing options:


Call the office for other options 301-866-1433.


Call Us or Email Us


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




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