James Harrison's first mechanical ice-making machine began operation in 1851 on the banks of the Barwon River at Rocky Point in Geelong, Australia. His first commercial ice-making machine followed in 1853, and his patent for an ether vapor compression refrigeration system was granted in 1855. This novel system used a compressor to force the refrigeration gas to pass through a condenser, where it cooled down and liquefied. The liquefied gas then circulated through the refrigeration coils and vaporized again, cooling down the surrounding system. The machine produced 3,000 kilograms (6,600 lb) of ice per day.[citation needed]
An air conditioning system, or a standalone air conditioner, provides cooling and humidity control for all or part of a building. Air conditioned buildings often have sealed windows, because open windows would work against the system intended to maintain constant indoor air conditions. Outside, fresh air is generally drawn into the system by a vent into the indoor heat exchanger section, creating positive air pressure. The percentage of return air made up of fresh air can usually be manipulated by adjusting the opening of this vent. Typical fresh air intake is about 10%.
Whether you have an electric or gas furnace, you shouldn’t have to suffer when your heater is not working. At Sears Home Services, our technicians fix many of the top furnace manufacturers. The issues you may face with your furnace can vary depending on the type of heating system. If you own an electric model and it isn’t working, some of the potential causes include:
Heating, ventilation, and air conditioning (HVAC[1]) is the technology of indoor and vehicular environmental comfort. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics and heat transfer. "Refrigeration" is sometimes added to the field's abbreviation, as HVAC&R or HVACR or "ventilation" is dropped, as in HACR (as in the designation of HACR-rated circuit breakers).

The use of CFC as a refrigerant was once common, including the refrigerants R-11 and R-12 (sold under the brand name Freon-12). Freon refrigerants were commonly used during the 20th century in air conditioners due to their superior stability and safety properties. When they are released accidentally or deliberately, these chlorine-bearing refrigerants eventually reach the upper atmosphere.[60] Once the refrigerant reaches the stratosphere, UV radiation from the Sun homolytically cleaves the chlorine-carbon bond, yielding a chlorine radical. These chlorine radicals catalyze the breakdown of ozone into diatomic oxygen, depleting the ozone layer that shields the Earth's surface from strong UV radiation. Each chlorine radical remains active as a catalyst until it binds with another radical, forming a stable molecule and quenching the chain reaction.
The use of CFC as a refrigerant was once common, including the refrigerants R-11 and R-12 (sold under the brand name Freon-12). Freon refrigerants were commonly used during the 20th century in air conditioners due to their superior stability and safety properties. When they are released accidentally or deliberately, these chlorine-bearing refrigerants eventually reach the upper atmosphere.[60] Once the refrigerant reaches the stratosphere, UV radiation from the Sun homolytically cleaves the chlorine-carbon bond, yielding a chlorine radical. These chlorine radicals catalyze the breakdown of ozone into diatomic oxygen, depleting the ozone layer that shields the Earth's surface from strong UV radiation. Each chlorine radical remains active as a catalyst until it binds with another radical, forming a stable molecule and quenching the chain reaction.
A contactor is a $25 mechanical relay that uses low-voltage power from the thermostat to switch 220-volt high-amperage current to the compressor and condenser fan. AC contactors can wear out and are at the top of the list of common air conditioning service failures. Even if your contactor is working, it pays to replace it every five years or so. Unscrew the old contactor before removing the wires. Then move the wires to the new unit (photo 6).
In the United States, HVAC engineers generally are members of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), EPA Universal CFC certified (for installation and service of CFC HVAC devices), or locally engineer certified such as a Special to Chief Boilers License issued by the state or, in some jurisdictions, the city. ASHRAE is an international technical society for all individuals and organizations interested in HVAC. The Society, organized into regions, chapters, and student branches, allows exchange of HVAC knowledge and experiences for the benefit of the field's practitioners and the public. ASHRAE provides many opportunities to participate in the development of new knowledge via, for example, research and its many technical committees. These committees typically meet twice per year at the ASHRAE Annual and Winter Meetings. A popular product show, the AHR Expo, is held in conjunction with each winter meeting. The Society has approximately 50,000 members and has headquarters in Atlanta, Georgia.
We are open from 7am to 10pm every weekday and from 7am to 8pm on weekends. We book appointments in a 2 hour arrival window and call 30-45 mins before we arrive so you do not have to sit around waiting. It is often possible to schedule your appointment in the evening or morning hours to avoid conflicting with your work schedule. Are you looking for service today? Give us a call or click on one of the Schedule Service buttons found on the top and left sides of this page to contact us today.

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HVAC is an important part of residential structures such as single family homes, apartment buildings, hotels and senior living facilities, medium to large industrial and office buildings such as skyscrapers and hospitals, on ships and submarines, and in marine environments, where safe and healthy building conditions are regulated with respect to temperature and humidity, using fresh air from outdoors.

When the time comes to schedule furnace repairs, you want a team you can trust. Keeping your home warm and comfortable is important for you and your family, which is why you should rely on the highly-trained team of technicians at Horizon Services. Our techs undergo at least 150 hours of technical training every year and are up-to-date on the latest, most advanced techniques in the trade. We also background-check all of our employees to ensure your complete comfort and safety. When you call on us for furnace repair, we will arrive on-time and on schedule, ready to resolve the issue as quickly as possible.

With the ice and snow in the Charlotte area this week be sure to look at your outdoor unit for ice or snow buildup, especially if you have a heat pump. You can carefully attempt to remove any frozen buildup by pouring warm water over the unit to melt the snow and ice. Do not use any sharp objects to pick or knock the ice off, this could cause severe damage to the unit

The chill of winter can be a scary thought when your furnace needs repair. When the furnace in your home goes on the fritz, you need it fixed right away to keep your family safe and comfortable. Every BGE HOME technician is licensed and adheres to a stringent in-house certification program that guarantees their knowledge, affirms their commitment to the customer, and ensures excellence in completing every furnace repair with the highest level of quality.

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