Dettson – A member of the Ouellet group. Mission. Provide sustainable solutions to the HVAC (heating, ventilation, air conditioning) industry.

With around 600 colleagues, Deutsche Messe organizes more than 150 trade fairs and events at home and abroad every year. It is a global event organizer whose events and services have been bringing together exhibitors and visitors since 1947. Deutsche Messe has helped numerous small enterprises to become world market leaders, while at the same time supporting large-scale enterprises on their road to further expansion.

Devard's Air Conditioning & Heating, Plumbing and Electrical offers affordable, reliable, energy-efficient, commercial and residential plumbing, air conditioning, heating and air conditioning units for the Dallas - Ft. Worth area with their '100% customer satisfaction policy', which is their company motto and what has led to their success.

Dexen supplies heating components to OEMs in HVAC and Hearth industries. They are also renowned providers of gas control systems and remote monitoring systems for the HVAC industry. Their products include gas valves (millivolt, 3V, 6V, 24V), electronic ignition control modules, pilots and supplemental components. Our services are in quality management, warehousing, logistics, engineering consulting and custom applications.

Dexter + Chaney provides web-based software that allows contractors to get work done anywhere using any device, and without the need to download any software.

Dexwet Holdings Corp. is an air filter manufacturing and technology company with more than 60 patents, the first of which was filed in 2000 to mitigate fine dust particles effectively. Dexwet was built on a mission to have a positive effect on health by providing clean air for humans and machines.

DFW IT Partner is a Reliable IT Partner providing one-stop IT solutions in Dallas, Austin, Fortworth, Houston, and San Antonio, Texas, USA. They provide businesses with the expertise, resources, and support needed to drive innovation and stay ahead of the competition in today’s fast-paced digital landscape. By working with them, businesses can achieve their technology innovation goals more efficiently and effectively.

DHL Group is the world's pioneer logistic company. The DHL Group connects people and markets and is an enabler of global trade. It aspires to be the first choice for customers, employees and investors worldwide. To this end, the Group focuses on growth in its profitable core logistics businesses and accelerating the digital transformation in all business divisions.

Founded in 1988 with offices in Kansas City, Austin and Denver, Dialectic is a non-traditional mechanical, electrical and plumbing engineering firm that brings buildings to life. With deep expertise in a range of verticals – including distribution, cannabis, multifamily, senior living and retail/restaurants – they know that true success comes with partnering as an extension of the team.

Digi-Key is one of the fastest-growing distributors of electronic components in the world. Digi-Key offers the world’s largest selection of electronic components in stock and available for immediate shipment. From prototype to production, they are here to fuel innovation all over the world.

DigiCert is the only provider of enterprise-grade SSL, IoT and PKI solutions. The world’s top banks, e-commerce retailers, healthcare providers, manufacturers and technology companies rely on us to secure their digital properties and to protect the privacy and data integrity of their consumers. Computerworld named DigiCert one of the Top 100 Places to Work in IT.

Digital Twin Consortium is a global ecosystem of users ,who are driving best practices for digital twin usage and defining requirements for new digital twin standards. It coalesces industry, government and academia to drive consistency in vocabulary, architecture, security and interoperability of digital twin technology. It advances the use of digital twin technology from aerospace to natural resources.

Since their company's beginning in 1946, they have been dedicated to providing exceptional service and superior heating, ventilation and air conditioning service and systems to East Texas residents at home and work. Customer satisfaction is their #1 priority.

DM Select Services has proudly provided heating, cooling and plumbing services to clients all around the Northern Virginia (NOVA) area since 2009. We have physical offices located all over the NoVA area in Ashburn, Burke, Fairfax Station, Leesburg, and Winchester, so we can meet you wherever you are located. Our team brings a wealth of HVAC experience and is focused on delivering quick turnaround times on our installations at an affordable price.

DNV GL is a global quality assurance, software solutions and risk management company. They provide classification, technical assurance, software and independent expert advisory services to the maritime, oil & gas, power and renewables industries. They also provide certification, supply chain and data management services to customers across a wide range of industries.

Done-Rite Plumbing & Rooter is the premier plumbing company in Orange, California, USA. They are a full-service plumbing contractor offering everything from water heater installation & repair, drain cleaning sewer line repair & installation, and general plumbing services. They service the entire Orange County area and can be out to any property in the area same-day for plumbing services.

Donnelly is the most reliable mechanical contractor in New York City. Donnelly gives the clients peace of mind. Donnelly does this by providing the most innovative services and solutions through the experienced team. New York City’s premier provider of HVAC service, maintenance, and construction, as well as energy solutions.

Donovan & Sons, Inc. provides a full range of plumbing, heating, ventilation and cooling services for both residential and commercial customers. The company is made up of 5th generation plumbers and HVAC technicians dedicated to providing their customers with prompt, reliable, professional services.

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.

Safe-T-Flush by Drain Shield is the new standard for condensate drain management, preventing leaks and clogs by ensuring a natural flow of condensation out of the drain line. The Safe-T-Flush system eliminates repetitive service calls, improve air quality with the unit, and prevent extensive and costly property damage.

Drake Refrigeration, Inc. is one of the best industrial chiller manufacturers. design custom industrial process chillers to meet a customer's particular .

Dring Air Conditioning & Heating is a family-owned business which makes them a rare breed in this era of big box stores and Internet commerce. They first opened their doors in 1953, and as their core of loyal HVAC heating and cooling customers has grown, their area of service has expanded.

DT Air Conditioning & Heating is Texas' renowned expert heating and cooling company. They offer furnace and air conditioning services in and around Plano, Texas, USA.

Ducane is all about providing outstanding value in home heating and cooling. They provide residential heating and cooling products, packaged units, and split systems under 5-tons.

Duct & Vent Cleaning of America, Inc. was founded in April of 1989 by Ron Eckman. As early as February of 1990, Duct & Vent Cleaning of America, Inc. joined NADCA, the HVAC Inspection, Maintenance and Restoration Association. In fact, they were the first company to be allowed membership that used portable hepa vacuums in the cleaning process.

For over 30 years, Duct Doctor USA has been providing quality air duct cleaning for both residential and commercial customers. Duct Doctor was founded by a board-certified allergist in 1985 with a mission to improve the air quality of homes and workplaces.

At Duct Hygiene they specialize in the servicing of commercial kitchen extraction systems, fresh air ventilation and Fire Damper Inspection & Testing. They provide maintenance services to both blue chip and private sector clients throughout the UK, performing over 7,500 service visits each year maintaining building safety and compliance.

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.