Ofgem is Britain’s independent energy regulator. Their role is to protect consumers now and in the future by working to deliver a greener, fairer energy system. They are a non-ministerial government department and an independent National Regulatory Authority.

For more than half a century, OJ Electronics have been designing and developing electronic controls for electric underfloor heating and HVAC Controls & Drives. They give access to deep application knowledge and innovative power and help differentiate themselves in the market. They are here to help build their customers’ business.

Oklahoma Chiller Corporation is a commercial and industrial HVAC company with offices in Tulsa and Oklahoma City. In addition to mechanical and HVAC services, Oklahoma Chiller offers building automation services and equipment rental services.

OklahomaGroup offers premier sales representation to all sectors of the HVAC and Refrigeration markets throughout the state of Oklahoma. Account Managers are dedicated to customer's needs and are supported by market and sales specialists.

Okto International, a HVAC provider has been working with the mission is to operate their company under Christ-like principles & standards; with integrity, honor; and work ethic. They are a highly respected service provider in the areas of Heating and Air-Conditioning all over Houston with installation, repair and maintenance.

Olans Heating and Air Conditioning, based out of Alabama, offers HVAC services, including Heating Services, Installation, Air Conditioning and Air Filtration. The goal of Olan’s Heating and Air Conditioning, Inc. is to provide a difference in the quality of services provided to his customers beyond other independent HVAC businesses.

Olimpia Splendid is an Italian company globally known for its design, production and marketing of products for Air Conditioning, Heating, and Air Treatment solutions.

A family owned business, Olson Comfort Services takes pride in offering the highest quality heating and cooling services. They are licensed, bonded, and insured.

Omdia unifies and harnesses the depth and breadth of expertise from Informa Tech’s legacy research brands: Ovum, IHS Markit Technology, Tractica and Heavy Reading. They offer unparalleled, world-class research and consultancy to navigate the now and create the future.

OMNIA Partners, Public Sector is the cooperative purchasing organization that is driving excellence in public sector procurement for K–12 schools and districts, state and local governments, colleges and universities and nonprofits. OMNIA Partners offers the most robust portfolio of high-quality cooperative contracts in the public procurement space.

OMS Machinery Co.,Ltd. is a High-Tech company, dedicated to the development and production of automatization, digitalization, and intelligentization equipment. Located in Zhongshan, Guangdong, OMS employs 80 professional engineers, and is well equipped with facilities. The company’s quality system and measurement system are ISO certified.

On Air services the South Palm Beach County areas, Broward County and North Dade County.We install and service all major and minor brand air conditioners, serving both Residential and Commercial Customers.

ONDA S.p.A. is manufacturing company of advanced heat exchangers for refrigeration, heating and air conditioning equipment.

One Call Heating and Cool is a Georgia-based Air Conditioning, Heating, HVAC and Air Purification systems installation and services company.

One Hour Heating & Air Conditioning provides a wide range of HVAC services, including installation, maintenance and repair of air Conditioning Units, Heating, Furnaces, Air Quality, Thermostats, etc and is based out of USA.

One Hour Heating & Air Conditioning® of Lee's Summit is the most trusted source of HVAC services in the Lee’s Summit area. Their team of Lee's Summit heating and cooling technicians are highly trained and licensed, so that they can provide the best Lee’s Summit HVAC repairs, installation, and maintenance possible.

One Hour Heating & Air Conditioning of Lake Villa provides home owners throughout the Round Lake region with reliable and efficient HVAC services and solutions.

One Source Home Service, an Air Pros company, was founded on the premise of Integrity, Reliability, and putting the customers first. One Source Home Service is here to help the users with HVAC, ductwork, plumbing, electrical, and home energy needs in the Colorado Springs and Pueblo, CO areas.

One Source, Inc. provides complete building management services for commercial properties throughout San Diego. they work with clients in a wide variety of industries to coordinate services in every area of maintenance, from janitorial services to landscaping, high-pressure washing, carpet cleaning, window washing, junk removal, and much more.

Customers will often call when their home is uncomfortable and One Stop Heat & Air's goal is to provide them with fast, friendly, and efficient heating and or cooling services. Heating or cooling issues are never convenient, and they can also be stressful and expensive. One Stop aims to provide customers with the best service at a reasonable price.

ONICON Incorporated has been delivering market leading flow and energy measurement products since 1987. Their inventory includes hydronic insertion turbine flow meters, hydronic inline turbine flow meters, BTU meters, flow computers, vortex flow meters, electromagnetic flow meters. They have been delivering quality engineered flow and energy measurement instruments for hydronic heating and cooling systems for over 30 years.

Onset HOBO data loggers provide reliable, accurate data in energy monitoring applications, including HVAC systems monitoring, building energy audits, measurement and verification, and building commissioning.

Oozzio offers an one-stop-shop for HVAC supplies! Whether for appliance repair, HVAC business, or a DIY enthusiast, Oozzio has everyone covered. Discover top brands, heating, cooling systems, furnaces, mini splits, air conditioners & accessories at their stores. Their user-friendly website and powerful search tools are the most trusted source for residential & commercial HVAC equipment.

OpenTherm is a non-manufacturer-dependent system of communication between modulating HVAC appliances and room thermostats. It consists of a communication protocol and an interface specification. The OpenTherm communication protocol is primarily designed to control modulating heating appliances. The protocol is available to members of the OpenTherm Association only.

Optergy provides effective tools to help manage the building’s comfort conditions and improve tenant retention. By optimizing comfort conditions (temperature, humidity, and ventilation) they can ensure the tenants are happy and more productive.

Optima Heating and Air Conditioning has provided Melbourne homes and businesses with heating and cooling solutions for more than 30 years. Their extensive industry experience and strong supplier partnerships allow them to provide affordable heating, cooling, and ventilation solutions across residential and commercial projects.

Optimum Energy’s patented software and engineering expertise has helped customers reduce energy use in heating and cooling systems, the largest consumer of energy in buildings, by up to 50%. Their solutions combine technologically advanced HVAC optimization software with powerful cloud-based data analytics and world-class engineering support.

Orange Coast Plumbing is the best choice in Southern California for plumbing, heating, and air conditioning repair and installation.

Family owned by Dave and Kathy Ignasiak, Orchard Hill Mechanical offers 25+ years of experience as a full featured residential, commercial, agricultural, and industrial mechanical contractor.

Ordine's Air Conditioning And Heating Inc. stands out in the heart of Tampa Bay, Florida, as a distinguished family-owned and -operated AC company with a rich heritage spanning over 30 years and three generations. They pride themselves on their reliability, expertise, and customer-focused service, ensuring customers' heating, ventilation, and air conditioning needs are met with the highest standards.