In 1902, the first modern electrical air conditioning unit was invented by Willis Carrier in Buffalo, New York.[citation needed] After graduating from Cornell University, Carrier found a job at the Buffalo Forge Company. There, he began experimenting with air conditioning as a way to solve an application problem for the Sackett-Wilhelms Lithographing and Publishing Company in Brooklyn, New York. The first air conditioner, designed and built in Buffalo by Carrier, began working on 17 July 1902.[citation needed]


A split system is a combination of an indoor air handling unit and an outdoor condensing unit. The indoor air handling unit contains a supply air fan and an air-to-refrigerant heat exchanger (or cooling coil), and the expansion device. The outdoor condensing unit consists of a compressor and a condenser coil. Split-systems are typically found in residential or small commercial buildings. These systems have the highest energy efficiency rating (EER) of all the available AC systems. Manufacturers are required to take the EER rating a step further and provide a seasonal energy efficiency rating (SEER) for use by consumers. SEER ratings vary widely and range from 10 to 20. The higher the SEER rating, the more efficient the AC system operates. If heating is required, an alternate method of heating the interior of the building must be used, usually in the form of electric or gas heating.
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When you contract with Vredevoogd Heating & Cooling Grand Rapids MI, you can count on us to make safety our top priority. Your HVAC system is, of course, a major investment and integral to the functioning of your home; however, nothing is as important as the safety of each life within your home. We carefully inspect your system to ensure that it is functioning properly in order to guard against carbon monoxide poisoning or other system emergencies. We take the greatest care when installing your HVAC system, knowing that a perfect installation is the safest installation for your home. We follow our industry’s best practices concerning safety and will happily share our know how with you when it comes to safely maintaining your system between service appointments.  If you ever suspect a problem with your HVAC system, you hear strange noises or smell unpleasant odors, for instance, you can call us night or day, 24/7, to address your heating and cooling emergency. We’ll never leave you in the lurch! We are ready to provide service ASAP to ensure the safe operation of your HVAC system.
Acosta Heating & Cooling is your one-stop-shop for all of your indoor comfort needs. We’ve been serving the Charlotte area for over 45 years, and our customers are always treated with respect and professionalism. But with so many air conditioning and heating companies out there, how are you supposed to choose? It all starts with how a company treats their customers. Here at Acosta Heating & Cooling, you’ll always be treated like family. From a quick furnace repair to comprehensive air conditioning service, Acosta will always deliver. See below for some reasons why we’re the best air conditioning and heating service company in Charlotte and surrounding areas:
Evaporative coolers, sometimes called "swamp coolers", do not have a compressor or condenser. Liquid water is evaporated on the cooling fins, releasing the vapor into the cooled area. Evaporating water absorbs a significant amount of heat, the latent heat of vaporisation, cooling the air. Humans and animals use the same mechanism to cool themselves by sweating.
R407C is a zeotropic hydro-fluoro-carbon refrigerant and is a blend of difluoromethane (R32) providing the heat capacity, pentafluoroethane (R125) decreasing flammability and tetrafluoroethane (R134a) to reduce pressure. Difluoromethane serves to, pentafluoroethane andtetrafluoroethane. R407C was developed as a replacement for the ozone depleting R22.
Trane central air conditioners are often billed as the “Cadillac of HVAC systems” and that’s because it’s one of the most reliable brands in the business. Trane AC is known for upholding warranties and offers a standard 10-year warranty that covers both parts and labor. Trane products are often pricier than other HVAC brands, but as the old saying goes, “You get what you pay for.”

Keep your home comfortable all year round with Keep your home comfortable all year round with this high quality and efficient 14 SEER central heating and cooling heat pump system. This system is ideal for new or replacement residential or commercial applications and consists of the outdoor condenser indoor air handler with evaporator coil heat strip and 30 ...  More + Product Details Close


At Genz-Ryan, we are here for you 24 hours a day, 7 days a week so you can count on us for all your heating repair work in the Minneapolis area. Our furnace repair technicians are well-trained and experienced. They’re ready to take care of any heating issue that you may have. We are a Lennox Premier Furnace Dealer and provide expert furnace repair service for most of the Minneapolis/St. Paul area. For over 60 years we have been getting the job done right the first time.


Need 24-hour emergency furnace repair? We can provide that too. With our same-day service and live phone and online chat service available 24/7, we make your comfort our top priority. Heating and air conditioning should help you live a comfortable life, so let us help you make your home the most comfortable it has ever been. It’s easy, just grab your furnace repair coupon, then simply give us a call at 615-953-9885, chat or schedule an appointment with us online.


At BGE HOME, our customers trust our courteous and knowledgeable technicians to repair the most sophisticated heating and air conditioning system breakdowns. Every BGE HOME technician is licensed in their trade 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 heating and air conditioning repair with the highest level of quality.
Combustion gases are generated by the burners in your furnace and passed through a heat exchanger. Air from your home blows across the heat exchanger to be warmed. It is then blown through a system of ducts to distribute around your home. During warm seasons your heating system works with your central air conditioning. Air is cooled as it’s blown over your air conditioning unit’s cooling coil, often attached to the air circulating fan of the furnace, and then sent through the same air ducts throughout your home.
You can adjust for seasons: During the summer, you can have the air conditioner stay off during the cooler morning hours and start cooling the house as everyone gets up and starts moving around. During the winter, you can have your heater stay off while you are away at work and turn on about a half hour or so before you get home so that you are coming home to a nice, warm house.
Bigger is not necessarily better when it comes to HVAC systems, and smaller isn't always more efficient. If you have too small of a system, your system will be running constantly as it tries to keep up with the temperature. If you have too large of a system, it won't run long enough to keep up with the humidity. In order to handle both temperature and humidity efficiently, an HVAC system should run for around 30 minutes at a time. If your system is staying on too long or shutting off after only around 10 minutes, you are not getting efficient performance.
The first air conditioners and refrigerators employed toxic or flammable gases, such as ammonia, methyl chloride, or propane, that could result in fatal accidents when they leaked. Thomas Midgley, Jr. created the first non-flammable, non-toxic chlorofluorocarbon gas, Freon, in 1928. The name is a trademark name owned by DuPont for any chlorofluorocarbon (CFC), hydrochlorofluorocarbon (HCFC), or hydrofluorocarbon (HFC) refrigerant. The refrigerant names include a number indicating the molecular composition (e.g., R-11, R-12, R-22, R-134A). The blend most used in direct-expansion home and building comfort cooling is an HCFC known as chlorodifluoromethane (R-22).
Dehumidification (air drying) in an air conditioning system is provided by the evaporator. Since the evaporator operates at a temperature below the dew point, moisture in the air condenses on the evaporator coil tubes. This moisture is collected at the bottom of the evaporator in a pan and removed by piping to a central drain or onto the ground outside.

Service Experts Heating and Air Conditioning was built with the determination of delivering customers with the most excellent heating and cooling practices in the industry. Since its foundation, Donelson Air Service Experts in Nashville has been faithful to community, offering the first class HVAC (Heating, Ventilation, Air Conditioning) products and services in the area. If you are interested in more information about your regional HVAC leaders, give us a call at 615-953-9885 or set up an appointment with us online.
If you need help with your air conditioner or want to learn more about the types of air conditioners available for your home comfort needs, explore HVAC.com’s HVAC Contractor Directory. Through the directory, you’ll be connected with local cooling contractors who can answer your questions and help you determine the best system and best value for your home. Just enter your ZIP code to see local HVAC contractors near you!

In variable climates, the system may include a reversing valve that switches from heating in winter to cooling in summer. By reversing the flow of refrigerant, the heat pump refrigeration cycle is changed from cooling to heating or vice versa. This allows a facility to be heated and cooled by a single piece of equipment by the same means, and with the same hardware.


A gas that can be retrofitted into a refrigeration system designed for another, without major system changes. For example, R422D is a drop-in replacement for R22 in many applications. However, hydrocarbon refrigerants are NOT drop-in alternatives for most fluorocarbon refrigerants due to substantial system changes needed to manage their differing characteristics (e.g. flammability).
What happens when you have an emergency? The first reaction of most people is to panic. When a furnace stops working, you need it fixed and fixed immediately—especially in the middle of a cold, Ohio winter. That need can make people feel as if they are at the mercy of the repair company. That is why it is so important to call a company you can trust and rely on—Jennings Heating and Cooling.
Inside the unit, the air passes over the evaporator coil first, and is cooled and dehumidified. The now dehumidified, cold air then passes over the condenser coil where it is warmed up again. Then the air is released back into the room. The unit produces warm, dehumidified air and can usually be placed freely in the environment (room) that is to be conditioned.
A mini-split system typically supplies air conditioned and heated air to a single or a few rooms of a building.[38] Multi-zone systems are a common application of ductless systems and allow up to 8 rooms (zones) to be conditioned from a single outdoor unit. Multi-zone systems typically offer a variety of indoor unit styles including wall-mounted, ceiling-mounted, ceiling recessed, and horizontal ducted. Mini-split systems typically produce 9,000 to 36,000 Btu (9,500–38,000 kJ) per hour of cooling. Multi-zone systems provide extended cooling and heating capacity up to 60,000 Btu's.
Reinstall the access panel and disconnect block. Turn on the circuit breaker and furnace switch. Then set the thermostat to a lower temperature and wait for the AC to start (see “Be Patient at Startup,” below). The compressor should run and the condenser fan should spin. If the compressor starts but the fan doesn’t, the fan motor is most likely shot. Shut off the power and remove the screws around the condenser cover. Lift the cover and remove the fan blade and motor (photo 7). Reinstall the blade and secure the cover. Then repower the unit and see if the fan starts. If it doesn’t, you’ve given it your best shot—it’s time to call a pro.
The performance of vapor compression refrigeration cycles[24] is limited by thermodynamics. These air conditioning and heat pump devices move heat rather than convert it from one form to another, so thermal efficiencies do not appropriately describe the performance of these devices. The Coefficient-of-Performance (COP) measures performance, but this dimensionless measure has not been adopted. Instead, the Energy Efficiency Ratio (EER) has traditionally been used to characterize the performance of many HVAC systems. EER is the Energy Efficiency Ratio based on a 35 °C (95 °F) outdoor temperature. To more accurately describe the performance of air conditioning equipment over a typical cooling season a modified version of the EER, the Seasonal Energy Efficiency Ratio (SEER), or in Europe the ESEER, is used. SEER ratings are based on seasonal temperature averages instead of a constant 35 °C (95 °F) outdoor temperature. The current industry minimum SEER rating is 14 SEER.[25]
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.
The amount of time air duct cleaning takes can depend on how extensive your duct system is, how old your air ducts are, and whether they have ever been cleaned. On average, expect a standard size home (between 2,000 and 3,000 square feet) to take 2-5 hours for one to two technicians to clean. Here are the proper protocol and equipment you should expect from a professional duct cleaning service, as recommended by the Environmental Protection Agency:
Whether it’s AC repair or total AC system replacement, there are various terms within the HVAC industry that can get confusing for homeowners. Not to mention all of the different pieces of heating and air conditioning equipment that can be used to boost your home’s energy efficiency and air quality. Of course we can’t write about all of the variations in a short blog post, so we’ll take a look at one of the routine inquiries we see at Service Experts Heating & Air Conditioning: what’s the difference between an air conditioner and an air handler?
Serving Families in Green Valley, Sahuarita & the Surrounding Communities since 1968, Green Valley Cooling & Heating has built a solid reputation for reliable and affordable temperature control solutions.  We create healthier and more comfortable indoor environments, protect against energy waste, and ensure sustainable performance through skilled service, quality products, and proven strategies.  No matter what type of challenge you’re faced with, count on Green Valley Cooling & Heating for expert assistance and sustainable results.  We provide new heating/cooling system installation, replacement, seasonal maintenance, prompt repair, air quality analysis, and energy saving opportunities to homeowners across Green Valley, Tubac, Vail, Corona de Tucson, Sahuarita & Amado.

In the case of heated water or steam, piping is used to transport the heat to the rooms. Most modern hot water boiler heating systems have a circulator, which is a pump, to move hot water through the distribution system (as opposed to older gravity-fed systems). The heat can be transferred to the surrounding air using radiators, hot water coils (hydro-air), or other heat exchangers. The radiators may be mounted on walls or installed within the floor to produce floor heat.
At the state level the rebates are still substantial. For example, switching to a zoned system can get you a $100 rebate from various A/C companies, and state rebates are also included. In Pennsylvania a high-efficiency air conditioner alone can get you up to $300, and a high-efficiency complete HVAC system can see up to $1000. Maryland's incentives get up to $1,250, with a $100 rebate on a tune up of an existing system.
Modern refrigerants have been developed to be more environmentally safe than many of the early chlorofluorocarbon-based refrigerants used in the early- and mid-twentieth century. These include HCFCs (R-22, as used in most U.S. homes before 2011) and HFCs (R-134a, used in most cars) have replaced most CFC use. HCFCs, in turn, are supposed to have been in the process of being phased out under the Montreal Protocol and replaced by HFCs such as R-410A, which lack chlorine.[14] HFCs, however, contribute to climate change problems. Moreover, policy and political influence by corporate executives resisted change.[15][16] Corporations insisted that no alternatives to HFCs existed. The environmental organization Greenpeace provided funding to a former East German refrigerator company to research an alternative ozone- and climate-safe refrigerant in 1992. The company developed a hydrocarbon mix of isopentane and isobutane, but as a condition of the contract with Greenpeace could not patent the technology, which led to its widespread adoption by other firms.[17][18][19] Their activist marketing first in Germany led to companies like Whirlpool, Bosch, and later LG and others to incorporate the technology throughout Europe, then Asia, although the corporate executives resisted in Latin America, so that it arrived in Argentina produced by a domestic firm in 2003, and then finally with giant Bosch's production in Brazil by 2004.[20][21]
Energy efficiency can be improved even more in central heating systems by introducing zoned heating. This allows a more granular application of heat, similar to non-central heating systems. Zones are controlled by multiple thermostats. In water heating systems the thermostats control zone valves, and in forced air systems they control zone dampers inside the vents which selectively block the flow of air. In this case, the control system is very critical to maintaining a proper temperature.
In addition, if water is condensed in the room, the amount of heat previously needed to evaporate that water also is re-released in the room (the latent heat of vaporization). The dehumidification process is the inverse of adding water to the room with an evaporative cooler, and instead releases heat. Therefore, an in-room dehumidifier always will warm the room and reduce the relative humidity indirectly, as well as reducing the humidity directly by condensing and removing water.
Refrigerant 22 (R-22 or MonoChloroDiFlouroMethane, CHClF2) is one of the most common refrigerants and is used in a wide variety of applications such as refrigeration, aerosol propellants, cleaning solvents, and foaming agents for plastics. This refrigerant is believed to be partially responsible for damaging the earth’s ozone layer and it’s use is being phased out over the next two decades. The ozone layer is a result of sunlight reacting with oxygen to produce a layer in the stratosphere more than 10 km above the earth’s surface. As R-22 refrigerant escapes from an AC system through leaks or is released into the atmosphere by other means, the R-22 molecule containing the chlorine atom (“monochloro”) rises in the atmosphere. Sunlight breaks down the R-22 molecule to yield a free chlorine radical (Cl-). The free chlorine radical combines with ozone (O3), decomposing it into normal oxygen (O2).
Furnace Circuit Board -- The furnace circuit board controls a variety of functions. It not only handles the regular operation of the furnace, it also monitors the furnace's various safety circuits. Over time, vibrations from the furnace can weaken solder point and cause them to separate. Dirt and debris can cause short-circuits that damage the board. Failure of the circuit board can cause a variety of effects ranging from the fan not turning on to the complete shutdown of the furnace.
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:

Ventilation is the process of changing or replacing air in any space to control temperature or remove any combination of moisture, odors, smoke, heat, dust, airborne bacteria, or carbon dioxide, and to replenish oxygen. Ventilation includes both the exchange of air with the outside as well as circulation of air within the building. It is one of the most important factors for maintaining acceptable indoor air quality in buildings. Methods for ventilating a building may be divided into mechanical/forced and natural types.[16]
Nerthlings Heating and Air Conditioning is proud to be rated as Erie, PA’s leading heating and cooling company. We’ve been serving Erie PA and the surrounding areas for over 60 years, handling all of their HVAC needs. For furnace repair, furnace service, or a new heating system installation at your home/business, Nerthling’s is the company to call if you want the job done right. We are also experts at AC repair, service & installation, as well as generator installation. Our other services include boiler repair and service, geothermal HVAC, heat pumps and ductless heating & air conditioning. To learn more about our high-quality HVAC services, give us a call today at 814-240-2297!
Another HVAC system used for central heating is the heat pump. A heat pump is a single unit that provides both heating and cooling. Heat pumps can be split or packaged. If the unit is split, that means the evaporator coil is housed in a cabinet inside of your house, while the rest of the unit is in a separate cabinet outside. On the other hand, with a packaged unit the entire heat pump is housed in a metal cabinet outside.

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:
They are also often harder to install. A proper location on the roof must be selected that can support the weight of the unit. Then a platform must be built and a drain pipe for the unit must be run along the roof to avoid problems with mold and corrosion. A crane must be used to lift the unit onto the roof while a team guides it into place and hooks it up.
We take great pride in our crew, choosing the best and brightest to represent R.S. Andrews in the face of an emergency. Our HVAC contractors boast not only unparalleled skill but also a friendly and professional demeanor. All of our work comes completely guaranteed, and we won’t rest until your emergency has been resolved to your full satisfaction!
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Advantages of the ductless system include smaller size and flexibility for zoning or heating and cooling individual rooms. The inside wall space required is significantly reduced. Also, the compressor and heat exchanger can be located farther away from the inside space, rather than merely on the other side of the same unit as in a PTAC or window air conditioner. Flexible exterior hoses lead from the outside unit to the interior one(s); these are often enclosed with metal to look like common drainpipes from the roof. In addition, ductless systems offer higher efficiency, reaching above 30 SEER.[39]
According to a 2015 government survey, 87% of the homes in the United States use air conditioning and 65% of those homes have central air conditioning. Most of the homes with central air conditioning have programmable thermostats, but approximately two-thirds of the homes with central air do not use this feature to make their homes more energy efficient.[56]
As a full-service heating contractor, we strongly encourage you to be vigilant with annual heating maintenance. Without proper maintenance, a heat pump, furnace or boiler might last only half as long as a well-maintained unit. Don’t tempt fate by skimping on annual service. We offer an economical, yet comprehensive maintenance agreement that we call our Cool Care Service Agreement. With our maintenance agreement you’ll receive:
"Very impressed. Returned call within 24 hours. They came out the same day I spoke with them and made the repair within 25 minutes. Very low service call fee. I had another repair service out two weeks earlier and after 3 service calls and the central air still not fixed and temperatures in the high 90's, it was such a relief to have a company identify the problem, have the necessary part with them and fix the problem."
HVAC professionals in the US can receive training through formal training institutions, where most earn associate degrees. Training for HVAC technicians includes classroom lectures and hands-on tasks, and can be followed by an apprenticeship wherein the recent graduate works alongside a professional HVAC technician for a temporary period.[31] HVAC techs who have been trained can also be certified in areas such as air conditioning, heat pumps, gas heating, and commercial refrigeration.[32]
According to a 2015 government survey, 87% of the homes in the United States use air conditioning and 65% of those homes have central air conditioning. Most of the homes with central air conditioning have programmable thermostats, but approximately two-thirds of the homes with central air do not use this feature to make their homes more energy efficient.[56]
Circulating refrigerant vapor enters the compressor, where its pressure and temperature are increased. The hot, compressed refrigerant vapor is now at a temperature and pressure at which it can be condensed and is routed through a condenser. Here it is cooled by air flowing across the condenser coils and condensed into a liquid. Thus, the circulating refrigerant removes heat from the system and the heat is carried away by the air. The removal of this heat can be greatly augmented by pouring water over the condenser coils, making it much cooler when it hits the expansion valve.
This single phase 13 SEER split system sweat This single phase 13 SEER split system sweat air conditioning system is designed for residential and commercial applications and consists of the outdoor condenser indoor cased coil and 30 ft. line set. The compact micro-channel condenser is charged with R-410A refrigerant and has a top air discharge. The cased coil ...  More + Product Details Close

With colder weather on its way back to Waldorf, furnace and heating repair may not be the first thing you think about, but maybe it should be. Sure, it’s easy for us to sit here and tell you to schedule annual furnace service, but it’s only because we want to help you avoid a heating breakdown during the coldest day of the month in Waldorf. Day or night, our HVAC experts are here to make sure you have a comfortable home, and can help get your furnace back running in little time.

Arundel Cooling has been proudly providing HVAC services in Columbia, Maryland for more than 40 years now. With this much experience, we bring our extensive knowledge and expertise to every HVAC repair or installation job we complete. No matter what time of day, Arundel Cooling and Heating will be there for you. We make ourselves available 24 hours a day, 7 days a week, so whether you need to schedule an appointment or you’re having a heating and cooling emergency, you can count on Arundel Cooling and Heating.

While there's nothing you can do to guarantee your air conditioner or furnace will never need repairs, there are ways to take better care of your system. Changing out the air filters every 3-6 months, making sure nothing is obstructing or interfering with the outside unit, and keeping all vents unblocked in well-used rooms will help keep your air conditioning and heating system operating efficiently.

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