Do you need expertise in HVAC? Roswell and Marietta residents who choose Moncrief Heating & Air Conditioning get the benefit of over 118 years of reputable experience in air conditioning and furnace repair, service and installation. Whether you have an emergency or need routine service, we are available 365 days a year. Call us today at 404-350-2300.


The professionals here at Brothers Plumbing, Heating and Electric are well trained, experienced and seasoned experts. We have been the go-to plumbing, electrical and HVAC company in the area for over 35 years and we always come highly recommended by our many satisfied customers. We offer a 100% satisfaction guarantee, have an A+ Rating with the BBB, won the Thornton “People’s Choice Award” for 2016, drug test and background check all of our employees, email you a picture of the technician who will be providing the service before arrival and call once the service is complete to ensure 100% satisfaction. So what are you waiting for? With our competitive pricing, trained and experienced technicians, and well-rounded list of home services, we’re clearly the company to trust. Get in touch with us here at Brothers Plumbing, Heating and Electric to schedule your needed service today!
The most recognized standards for HVAC design are based on ASHRAE data. The most general of four volumes of the ASHRAE Handbook is Fundamentals; it includes heating and cooling calculations. Each volume of the ASHRAE Handbook is updated every four years. The design professional must consult ASHRAE data for the standards of design and care as the typical building codes provide little to no information on HVAC design practices; codes such as the UMC and IMC do include much detail on installation requirements, however. Other useful reference materials include items from SMACNA, ACGIH, and technical trade journals.
If you find yourself having a more traditional concern, we can help with that as well. Whether you’re looking to upgrade to a more energy efficient system, require an emergency furnace repair, or need to schedule an annual appointment, we’re here to help. We can tackle any issue or concern that you may have with your HVAC system. Our team will give you confidence and peace of mind when it comes to your HVAC system.

A true central air-conditioning system uses ducts to distribute cooled air throughout the house. In a “split system,” the most common design, refrigerant circulates between an indoor coil and a matching—meaning from the same brand—outdoor condenser with compressor (see illustration, below). The refrigerant cools the air, dehumidifying it in the process; a blower circulates air through ducts throughout the house. A thermostat maintains the temperature at the setting you select. A variation is the “heat pump,” a type of system that functions as heater and air conditioner.
There are a number of claims in the HVAC industry that make HVAC technicians sound like they know what they are doing, but the North American Technician Excellence (NATE) certification program is the only closed book examination and certification program, administered by a third party, that tests real world working knowledge of HVAC systems. That's why all of our service technicians complete and continue NATE certification training throughout their career with SMO.

Smyrna homes and businesses have relied on Coolray for air conditioning service and installation since 1966. We can provide repair and maintenance on all makes and models of air conditioners for your home or business and offer 24 hour emergency AC repair service. We also offer a wide range of new air conditioning systems and our expert air conditioning technicians can help you select an air conditioner or heat pump that is right for your home and budget.

The main problem when installing a multi-split system is the laying of long refrigerant lines for connecting the external unit to the internal ones. While installing a separate split system, workers try to locate both units opposite to each other, where the length of the line is minimal. Installing a multi-split system creates more difficulties, since some of indoor units can be located far from the outside. The first models of multi-split systems had one common control system that did not allow you to set the air conditioning individually for each room. However, now the market has a wide selection of multi-split systems, in which the functional characteristics of indoor units operate separately from each other.


With that being said, we ask ourselves, “How do we ensure our customers that we are the company they can count on?”. It all starts with our people. Each of our team members have passed a criminal background and drug test, so you can trust them with your home and family. We are licensed and insured well beyond the minimum requirements set for by the State of Texas. Also, we provide continuous training for both the technical and customer service aspects of our industry. We do this in order to make sure that we are ready and able to serve your needs with excellence.

Heat pumps are similar to cooling only systems with one exception. A special valve in the refrigeration piping allow the refrigeration cycle to be operated in reverse. A cooling only system cools the indoor air and rejects heat to the outdoors. A heat pump can also cool the indoor air, but when the valve is reversed, the indoor air is heated. A supplementary electric resistance heater may also be used to assist the heat pump at lower outdoor temperatures. In colder climates, heat pumps require a defrost period. During defrost times the electric heater is the only means of heating the interior of the building. These units are manufactured as either split or packaged systems.
The 2nd-century Chinese mechanical engineer and inventor Ding Huan of the Han Dynasty invented a rotary fan for air conditioning, with seven wheels 3 m (10 ft) in diameter and manually powered by prisoners of the time.[6] In 747, Emperor Xuanzong (r. 712–762) of the Tang Dynasty (618–907) had the Cool Hall (Liang Dian 涼殿) built in the imperial palace, which the Tang Yulin describes as having water-powered fan wheels for air conditioning as well as rising jet streams of water from fountains. During the subsequent Song Dynasty (960–1279), written sources mentioned the air conditioning rotary fan as even more widely used.[7]
Relative humidity is the ratio of the partial pressure of water vapour in an air-water mixture to the saturated vapour pressure of water at a prescribed temperature. In prevailing Northern European conditions relative humidity and percentage saturation (ration of moisture content) can be considered the same as the divergence is <1%.  In high temperature areas they should be treated differently as the divergence may be as high as 10%.

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%.


Welzig Heating & Air is on call, 24 hours a day, 365 days, making sure that the skilled assistance you need is always available.   There’s no need to struggle with decreased performance from your air conditioner.   Even small aggravations, such as elevated sound levels, strange smells, or longer running times, are warning signs of larger issues and usually add up to higher running costs.   When you trust your cooling equipment to Welzig Heating & Air, we work to not only resolve pressing issues. but ensure reliability, efficiency, and longevity.   A thorough inspection often protects against degraded air quality, property damage, and premature system failure.   We work on all makes and models of air conditioners, and with every repair we tackle, our team of dedicated technicians earn your satisfaction.   Through exemplary customer service, ethical business practices, and exacting standards, Welzig Heating & Air provides superior solutions to homeowners across Boulder, Longmont, Louisville, Lafayette, CO & more.
The condensed, pressurized, and still usually somewhat hot liquid refrigerant is next routed through an expansion valve (often nothing more than a pinhole in the system's copper tubing) where it undergoes an abrupt reduction in pressure. That pressure reduction results in flash evaporation of a part of the liquid refrigerant, greatly lowering its temperature. The cold refrigerant is then routed through the evaporator. A fan blows the interior warm air (which is to be cooled) across the evaporator, causing the liquid part of the cold refrigerant mixture to evaporate as well, further lowering the temperature. The warm air is therefore cooled and is pumped by an exhaust fan/ blower into the room. To complete the refrigeration cycle, the refrigerant vapor is routed back into the compressor. In order for the process to have any efficiency, the cooling/evaporative portion of the system must be separated by some kind of physical barrier from the heating/condensing portion, and each portion must have its own fan to circulate its own "kind" of air (either the hot air or the cool air).
©2018 By Horizon Services, LLC. All Rights Reserved. DE License # PL0000726, HL0000299. Contractor Reg. # PA017876, PA057742. NJ Plumbing Lic. # PL36BI01232300 - David Geiger HIC reg. # 13VH05117300, NJ Master HVACR contractor Lic. # 19HC00193700. MD Master HVACR contractor Lic. # 47186, MD Master Plumber/Gas Fitter Lic. # 63739 – David Geiger. EL.LIC./B.P. #34EI01207700.
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).
SEER is useful for comparing one model to another much in the same way that a car's calculate MPG is useful. It's not an accurate prediction of exactly how efficient the system is, but it can tell you which one is more efficient. Also, since SEER is based on a "cooling season", what region you live in will determine how long or short your cooling season is.
Hospital operating theatres, in which air is filtered to high levels to reduce infection risk and the humidity controlled to limit patient dehydration. Although temperatures are often in the comfort range, some specialist procedures, such as open heart surgery, require low temperatures (about 18 °C, 64 °F) and others, such as neonatal, relatively high temperatures (about 28 °C, 82 °F).
©2018 By Horizon Services, LLC. All Rights Reserved. DE License # PL0000726, HL0000299. Contractor Reg. # PA017876, PA057742. NJ Plumbing Lic. # PL36BI01232300 - David Geiger HIC reg. # 13VH05117300, NJ Master HVACR contractor Lic. # 19HC00193700. MD Master HVACR contractor Lic. # 47186, MD Master Plumber/Gas Fitter Lic. # 63739 – David Geiger. EL.LIC./B.P. #34EI01207700.
In 1995, Germany made CFC refrigerators illegal.[22] DuPont and other companies blocked the refrigerant in the U.S. with the U.S. EPA, disparaging the approach as "that German technology".[21][23] Nevertheless, in 2004, Greenpeace worked with multinational corporations like Coca-Cola and Unilever, and later Pepsico and others, to create a corporate coalition called Refrigerants Naturally!.[22][24] Then, four years later, Ben & Jerry's of Unilever and General Electric began to take steps to support production and use in the U.S.[25] In 2011 the EPA decided in favor of the ozone- and climate-safe refrigerant for U.S. manufacture.[17][26][27]
Do you need expertise in HVAC? Roswell and Marietta residents who choose Moncrief Heating & Air Conditioning get the benefit of over 118 years of reputable experience in air conditioning and furnace repair, service and installation. Whether you have an emergency or need routine service, we are available 365 days a year. Call us today at 404-350-2300.
The contactor (relay) and start/run capacitor(s) (see illustration below) fail most often and are inexpensive. So it’s a safe bet to buy and install those parts right away, especially if your air conditioning service unit is older than five years. The condenser fan motor can also fail, but it runs about $150 — hold off buying that unless you’re sure that’s the culprit.
Established in 1988, T. N. Bowes Heating & Air Conditioning, Inc. provides a trusted source of new installation, replacement, seasonal maintenance, and prompt repair of heating, cooling, and air quality equipment in Leonardtown, Waldorf, Lusby, La Plata, St. Leonard, California, Prince Frederick, Hughesville & Hollywood, MD. As a Carrier Factory Authorized Dealer, our team is fully licensed, extensively trained, and consistently updated in a wide range of industry-leading options to meet any challenge. All projects are handled to your specifications and completed within a strict timetable.
Whenever you need any installation, repair, or maintenance for your heating system, call Baker Brothers. We are committed to providing the best customer service and getting your issues solved quickly and efficiently. We service all major make and models of electric and gas heating system in your home. Baker Brothers employs only the best heater/furnace service professionals that are ready to get your home comfortable for you during those cold days and nights.
The U.S. Environmental Protection Agency (EPA) requires this certification since appliances that use refrigerants can harm the ecosystem if they're not properly installed or maintained. While the EPA mandates this area of HVAC work, requiring a technician to get a license is up to the state to decide. With that said, not all states demand contractors to obtain one.
When your furnace needs immediate repair, trust the professionals at BGE HOME. We understand that furnace problems are more than a mere inconvenience – they can have a serious impact on the health and safety of you and your family. Our technicians are available 24-hours a day for emergency repairs. Click to schedule your repair and have peace-of-mind knowing that a licensed, certified HVAC technician will have your system up and running as quickly as possible. For 24-hour emergency furnace repair service, call 1-888-243-4663.
As a technical industry, the heating and cooling field is associated with annual advances. New energies make our industry an exciting place to work. Our team thrives on keeping up to date with all changes in the HVAC field. We are here to share our knowledge with each customer. When you are ready to update your HVAC system, we can help you select the ideal system for your home.
If you're in need of heat repair, furnace repair or heating repair then call the Ashburn HVAC Services family-owned and operated HVAC contractor in Leesburg and Ashburn, VA. We owe all of our success to you, our Ashburn and Leesburg customers who support us and we want to thank you! The highest compliment we receive is the trust in your referral and we truly appreciate your support!

Engineers have pointed out some areas where efficiency of the existing hardware could be improved. For example, the fan blades used to move the air are usually stamped from sheet metal, an economical method of manufacture, but as a result they are not aerodynamically efficient. A well-designed blade could reduce electrical power required to move the air by a third.[26]
An air conditioner's compressor contains a refrigerant. As it works, it sends this refrigerant through the system. As warm air blows across the coil that carries this refrigerant, the heat transfers to the refrigerant (cool always absorbs warm). A fan moves the cooled air through the ducting and out of vents that lead into the rooms of your house. The refrigerant returns to the compressor where the absorbed heat is moved outside. The refrigerant is then sent through the coil once again to continue the cycle.

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