Douglas Cooling & Heating is a full-service HVAC company that serves the higher Birmingham area. They strive hard to provide prompt and efficient solution.

Dowdle Heating and Air has been serving North MS since 1952. In 2012, Chris Powell merged with Dowdle to create Dowdle and Powell Heating and Air. They are an HVAC contractor. They offer service, sales, installation and fabrication of all HVAC equipment including air conditioners, thermostats, heat pumps, air filters, gas furnaces, programmable thermostats, humidifiers, ductless split systems.

Dowling Corporation is a pioneer HVAC/R mechanical services provider serving clients in New Hampshire, Southern Maine, and the North Shore of Massachusetts. Providing comfort and peace of mind since 1961.

Ductcap Products Inc. are renowned manufacturers of temporary reusable duct end covers. These duct end covers help keep duct work clean during shipping, staging and during construction.

DUCTZ has been providing industry-leading air duct cleaning and HVAC restoration services for residential and commercial properties alike.

Duke Energy is one of the largest energy holding companies in the United States. Its Electric Utilities and Infrastructure business unit serves approximately 7.5 million customers located in six states in the Southeast and Midwest.

Dust Free manufactures a wide variety of air purification equipment designed to help allergy patients in both residential and business locations. They also provide Ultra-violet (UVC) residential and commercial fixtures, Electrostatic air filters, room air purifiers, ceiling mounted air purification systems, industrial fan powered air cleaners, ultra-violet light fixtures and many more.

Dynamic Air Quality Solutions manufactures residential, commercial, and industrial high-performance IAQ systems that remove ultrafine particles, odors and gas phase contaminants, without Ozone.

Dynamic Filtration manufactures robust, industrial-grade EDM filters, long lasting cellulose industrial fluid filters and several popular waterjet filters.

Dynatemp International, Inc. is a privately held supplier of refrigerants and refrigerant recovery services. Dynatemp offers the HVAC/R market a portfolio of products, services, and market intelligence that is designed to increase long-term profitability, customer loyalty, and environmental stewardship.

E Instruments International by Sauermann designs, manufactures and markets a complete range of innovative instrumentation solutions encompassing Combustion Gas Analyzers, Emissions Analyzers, Indoor Air Quality, and Calibration equipment especially designed for the power, process, industrial, institutional, food, and HVAC markets.

East Coast Metals products, professional service centers, and technical support combine to give the user exceptional service before, during, and after the sale. They are dedicated to fulfilling this commitment every single day. Their mission is to deliver the quality HVAC products the user needs, when they need them, and provide expert technical support.

Eastside Heating & Air Conditioning, Inc., was started in 1966 by Vern Stoelting with a mission of furnishing his customers with the best in customer service and satisfaction. In 1969 Doug Turner joined Eastside as a service tech and later became a partner. Vern retired in 1981. In 1980 Randy Burke came to work at Eastside becoming a partner a few years later.

Eliminate expensive shutdowns with a copper tube emergency shut off valve. Replace failed valves or install a new valve for hot or cold water in less than 10 minutes without turning off the water. No More Draining Systems or Pipe Freezing. Just EasyFit.

Easyflex is the leader of all things flexible. We’re a global leading manufacturer and distributor of flexible, corrugated stainless steel products. Through technological innovation, attention-to-detail, and stringent quality control, we manufacture and deliver superior products to customers worldwide.

ECO Manufacturing provides Thermostats, controls and much more.

EcoMech Heating and Air Services specializes in high efficient heating and air systems, energy savings choices for its customers, custom duct designing for your system, and air quality. They are here to assist users with all of the energy savings needs

Edmonds Engineering is a full-service Mechanical, Electrical, and Plumbing Engineering design firm that partners with owners, architects and contractors to create trusted engineering solutions for commercial and industrial applications.

Elite Heating and Air is a trained HVAC specialist who is available to service all of the HVAC installation and maintenance needs They offer HVAC service plans to make sure that the heating and cooling equipment runs smoothly and efficiently.

Mesa Energy Systems, Inc. (dba EMCOR Services Mesa Energy) has provided its clients with high-quality mechanical, commercial HVAC, and building automation consulting and services that address the most compelling energy-related issues. They are commercial HVAC contractors with the knowledge and experience to also provide commercial refrigeration repair and chiller services.

Emerald Aire, Inc. and Sound Air, Inc. merged. Sound Air was basically a Sheet Metal Fabrication and Installation business and merged perfectly with all the mechanical, service, repair and piping escapades performed by Emerald Aire, Inc. Linda Dupuis-Fricke was the sole owner of Sound Air and became the President of the new business, Emerald Aire, Inc. Linda was president until she left the organization in 1999.

Thermostats, gas valves, ignition controls and ignitors, Filter Driers, Expansion Valves, and Solenoid Valves for heating, air conditioning, refrigeration and IAQ.

Emerson Swan is a nationally recognized, stocking manufacturer's representative organization serving the northeastern United States and the Greater Toronto Area. Emerson deals with different lines of products, including HVAC. Emerson Swan also provides timely market information, including market trends, conditions and all relevant market data to its manufacturers for forecasting and planning purposes.

EMI offers a comprehensive line of ductless air conditioning systems with equipment for both hydronic as well as refrigerant-based systems. With exceptional performance and operating economy, ductless split systems are the ideal solution for light commercial, institutional & residential applications.

Empire Heating and Air Conditioning, Inc. was founded in 1985 by Martin and Gila Hoover. Their main office is located in Decatur, Georgia with a satellite office in Cumming, Georgia. They service, install, and repair all makes and models of heating and air conditioning equipment including boilers, hydronic heating, heat pumps, and water heaters.

ENE Systems provides integration, engineering, and installation of building automation systems that provide return on investment to facility owners, and convenient turnkey solutions to mechanical contractors.

Energy Cloud Inc. is a clean-tech company focused on energy efficiency, sustainability, and healthy building environments. It helps customers save money and energy by managing and measuring electricity, water, and gas usage through our gMeter® platform, AI, and Hummingbird™ HVAC line of products.

Energy Professionals is one of North America’s Energy Consultants working with commercial customers to reduce and control their energy budgets, building client-specific, comprehensive energy strategies that factor in our client’s goals and objectives. As an energy consulting firm, they offer both focused solutions to a specific issue and broad plans to address long-term growth, paving the way for energy independence, providing more choice

Energy Resources Integration (ERI) provides engineering services including energy efficiency engineering and high level energy management support. ERI provides a range of services including energy audits, engineering studies, energy modeling, financial analysis, project management, and technical training so that you can reduce your energy spend.

Energy Vanguard's ultimate goal is to make homes better for the people who live in them and to reduce the negative impacts of buildings on the Earth.