Heating & AC Expertise on Long Island Since 1983

At DML & S Air Conditioning & Heating, we’re here to help your create and maintain a healthy indoor climate in your home or commercial property. As a full-service HVAC contractor, we provide both residential and commercial heating, cooling and indoor air quality products and services. Our family owned business has been serving Long Island, including Head of the Harbor, Smithtown, Miller Place and Mount Sinai NY, for over 30 years and we are proud of our reputation for professional, courteous and attentive service.

For all of your heating needs in East Setauket, Miller Place, Mount Sinai NY and the surrounding areas of Nassau and Suffolk counties, we are here to help!

What's New?

Replace your system and get up to $1,400 per unit in rebates with the PSEGLI Cool Homes Program. Only available through approved contractors. Learn more.