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.

Onsite Contractors & Plumbing Ltd is the trusted local expert for plumbing, gas fitting, and general contracting services in London. Whether it's residential or commercial, our licensed team delivers reliable, high-quality solutions on time and on budget. From renovations to emergency repairs, they’re here when users need them most.

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.

Nestled in the heart of Holiday, Florida, Ordine's Air Conditioning and Heating, Inc. has established itself as a premier air conditioning contractor dedicated to keeping homes and businesses comfortable all year round. With a wide array of services including AC installation, repair, and tune-ups, their experienced team ensures the cooling system operates at peak efficiency.

The history of the ORION dry pump started in Japan with the oil-free rotary vane vacuum pump. Thanks to its reduced noise and longer life, the dry pump has been indispensable in automation and labor-saving applications, playing an active and wide-ranging role for every kind of industry

OROKON are certified professionals in their field, specializing in the sale and installation of air conditioners, heat pumps, and recuperators. They strive to ensure the comfort and well-being of every customer, so they offer only the highest quality products and services at the best prices. They offer a wide range of air conditioners of various types and models, suitable for both homes and commercial premises.

Orell Filtration is based in Stalybridge and supplies Dust Extraction Equipment, Bulk Bags, Air Filters, Filtration Products, Filter Fabrics, Filter Sleeve Bags, Multipockets, and much more.

Over 25 years ago, Victor Orzech began an HVAC company out of a basement workshop in his home. The years have brought many changes, but one thing remains the same: a commitment to the highest level of service and installation in the HVAC industry.

As a full service Air Conditioning, Heating and Ventilation company, OSBORN AC and Heat has been delivering high standard HVAC services.

Osborn HVAC is a full service Sugar Land AC Company servicing both residential and commercial Air Conditioning, Heating and Refrigeration equipment. OSBORN HVAC has provided quality AC Repair, HVAC maintenance and AC installation throughout the Houston and surrounding area since 2009. Located in Sugar Land, Tx, they continue to service a growing community of satisfied customers who depend upon us for quality service.

Ottawa Home Services specializes in installations and repairs of furnaces, air conditioners and water heaters using professional, no-pressure cost estimates based on their actual needs and wants. They offer flexible financing and rental options, as well as on-time, 24/7 emergency service, so users never have to worry about going without one of their essential home systems.

Oventrop is one of the European manufacturers of valves and controls for the Building Services Industry. The company is an expert partner to stockists, consultants, contractors, and industry. Oventrop offers its partners a long-term beneficial relationship.

Over represents what every innovative company must be: Over and Above. Following this concept, it is set to establish a global standard for energy management and indoor air quality to make cities healthier, smarter, and more efficient. Over aim to be a pivotal resource with a collective effort to combat environmental issues mainly climate change and achieve energy efficiency within the UN Sustainable Development Goals.

Oversluizen distinguishes itself by developing and producing cooling solutions for the industry 1-on-1 with the client. In their own factory in Ridderkerk they calculate and produce the coolers for the project in-house.

Owen AC Services specialize in providing HVAC services, as well as air quality services. They work with air conditioners, providing installations, repairs, and maintenance, as well as heaters. They work with folks throughout Houston and the surrounding area, and they strive to ensure that home is comfortable, and its air remains fresh and healthy.

Owens Companies brings over six decades of experience to each building they service. They are the leading fully integrated, single-source mechanical contractor in the Twin Cities. Twenty-four hours per day, seven days per week, Owens is here for home or business.

Oxbox HVAC is a value‑focused residential and light‑commercial heating and cooling brand under Trane, offering affordable air conditioners, heat pumps, air handlers, and coils. They recently launched a low‑GWP R‑454B refrigerant split‑system line, highlighting their shift toward more sustainable, eco‑friendly HVAC solutions.

Oxygen8 is changing the way buildings provide healthy, comfortable and energy efficient spaces for occupants. They provide 100% fresh, filtered air and smart technology for maximum comfort and value.

Melbourne homeowners typically opt for multi-head split system air conditioning installations to cool down bedrooms and living areas. Oz Air generally recommend single or multi-split systems for most residential customers, depending on the design and construction of the building.

P & R Heating provides a wide range of installation and servicing such as mechanical installation, plant room renewals, heating installation (large and small scale), hot and cold water storage and distribution, plant control installations, gas and oil servicing and maintenance, periodic test and inspection, emergency lighting and much more.

PED Associates Inc. is a manufacturers’ representative company serving HVAC/R, appliance parts, wholesale distributor, OEM’s and exporters.