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]


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.
Air changes per hour Bake-out Building envelope Convection Dilution Domestic energy consumption Enthalpy Fluid dynamics Gas compressor Heat pump and refrigeration cycle Heat transfer Humidity Infiltration Latent heat Noise control Outgassing Particulates Psychrometrics Sensible heat Stack effect Thermal comfort Thermal destratification Thermal mass Thermodynamics Vapour pressure of water
Many disconnect blocks contain two cartridge fuses. Check them before you proceed with repairs (Photo 3). A blown fuse is a sign of a failing part inside the condensing unit. So don’t just replace it and think you’ve solved the problem. Instead, replace the parts we show here. Then install new fuses and fire up the unit. If it blows again, call a pro—you’ve got more serious issues.
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.
For more than sixty years, Nerthling's Heating and Air Conditioning has continued a tradition of superior customer service across Erie County, including Erie, Millcreek and Fairview.  Family owned and operated, we treat you, your home, and your comfort the way we would like to be treated.  This commitment to integrity extends to every service and product we provide.  Our goal is to deliver the highest rewards for your investment, whether you require installation, maintenance, or repair.  We offer a wide range of styles and sizes of equipment, services, and resources to help you achieve your goals for temperature control, air quality, and energy savings.
An energy recovery ventilator: This component helps improve the air inside your home by swapping it out with fresh air from the outside. During the winter months when houses are closed up to keep out the cold, the air inside becomes a handy way for colds and flu to infect an entire family. By circulating outside air inside, the health of your family will have a better chance.
In 1992, a non-governmental organization, Greenpeace, was spurred by corporate executive policies and requested that a European lab find substitute refrigerants. This led to two alternatives, one a blend of propane (R290) and isobutane (R600a), and one of pure isobutane.[18][22] Industry resisted change in Europe until 1993, and in the U.S. until 2011, despite some supportive steps in 2004 and 2008 (see Refrigerant Development above).[27][67]
Nothing is worse than having your furnace fail on the coldest night of the year. When your furnace needs a repair, you shouldn’t have to worry about the company providing your furnace repair services. You won’t have to – not when you give John Betlem Heating & Cooling a call. No matter what kind of furnace you own, our talented team of technicians are able to easily identify any problem your furnace might be having.
A specialized air conditioner that is used only for dehumidifying is called a dehumidifier. It also uses a refrigeration cycle, but differs from a standard air conditioner in that both the evaporator and the condenser are placed in the same air path. A standard air conditioner transfers heat energy out of the room because its condenser coil releases heat outside. However, since all components of the dehumidifier are in the same room, no heat energy is removed. Instead, the electric power consumed by the dehumidifier remains in the room as heat, so the room is actually heated, just as by an electric heater that draws the same amount of power.
The compressor-based refrigerant systems are air-cooled, meaning they use air to exchange heat, in the same way as a car radiator or typical household air conditioner does. Such a system dehumidifies the air as it cools it. It collects water condensed from the cooled air and produces hot air which must be vented outside the cooled area; doing so transfers heat from the air in the cooled area to the outside air.
Heating, Ventilating, and Air Conditioning (HVAC) equipment perform heating and/or cooling for residential, commercial or industrial buildings. The HVAC system may also be responsible for providing fresh outdoor air to dilute interior airborne contaminants such as odors from occupants, volatile organic compounds (VOC’s) emitted from interior furnishings, chemicals used for cleaning, etc. A properly designed system will provide a comfortable indoor environment year round when properly maintained.
Cleaning the debris that builds up on your filters will aid with the flow of air. When your air filter is clogged, your air handler must work harder to compensate for the blockage of air flow. In addition to driving up your utility bill, the reduced air flow through your heating and cooling system can cause your heat exchanger to overheat and shut off too quickly.    
Air duct cleaning is done by heating, ventilation and air conditioning (HVAC) professionals. The pros use industrial-strength, truck-mounted vacuums and powerful brushes and hoses to clean inside the metal ducts that make up your forced air heating and cooling system. The Environmental Protection Agency recommends duct cleaning if there is “substantial visible mold growth inside hard surface ducts, ducts that are infested with vermin such as rodents or insects, or ducts that are clogged with excessive amounts of dust and debris and/or particles are actually released into the home from your supply registers.”
The use of furnaces, space heaters, and boilers as a method of indoor heating could result in incomplete combustion and the emission of carbon monoxide, nitrogen oxides, formaldehyde, volatile organic compounds, and other combustion byproducts. Incomplete combustion occurs when there is insufficient oxygen; the inputs are fuels containing various contaminants and the outputs are harmful byproducts, most dangerously carbon monoxide, which is a tasteless and odorless gas with serious adverse health effects.[14]
Refrigeration air conditioning equipment usually reduces the absolute humidity of the air processed by the system. The relatively cold (below the dewpoint) evaporator coil condenses water vapor from the processed air, much like an ice-cold drink will condense water on the outside of a glass. Therefore, water vapor is removed from the cooled air and the relative humidity in the room is lowered. The water is usually sent to a drain or may simply drip onto the ground outdoors. The heat is rejected by the condenser which is located outside of room to be cooled.

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.
Electronically Commutated (EC) fans use brushless DC motors which include in-built electronics to convert the AC supply to DC without the need for a separate DC supply. EC fans provide a more efficient (up to 30%) means of airflow through Precision Air Conditioning (PAC) units with the additional benefit of variable speed control via an output signal from the unit controller. Also see EC Fan upgrades.
HVAC equipment is estimated to last about 15 to 20 years. Yet over the years, parts go out and need to be repaired. Heat sensors, exchangers, and ducts can become worn out. Air conditioning motors may need repairing from time to time. For repairs to your heating and air conditioning systems, and even general maintenance, let HomeAdvisor help. Enter your zip code and let us connect you with prescreened HVAC repair services near you.

As a Carrier® dealer, with a wide variety of products to choose from, we can keep your family healthy and feeling comfortable all year long. We carry a complete line of indoor comfort equipment with innovations that raise the standards of comfort and reliability, including air conditioners, heat pumps, gas furnaces, programmable thermostats, humidifiers, ductless split systems, geothermal systems, boilers, air cleaners, ultra violet lights, ventilators and zoning products. Let the experts at Dunes Heating and Air Conditioning, LLC help you customize a solution that's right for you.
Installing a split system may involve making modifications to the house itself for the necessary lines to be run. The heat exchangers are also more prone to picking up debris and must be cleaned on a regular basis. While they come with protective screens over the fan, care must still be taken to ensure that nothing gets in, especially in a home with children.
In the case of direct expansion equipment, the air passing over the indoor cooling coil heats the cold liquid refrigerant. Heating the refrigerant causes boiling and transforms the refrigerant from a cold liquid to a warm gas. This warm gas (or vapor) is pumped from the cooling coil to the compressor through a copper tube (suction line to the compressor) where the warm gas is compressed. In some cases, an accumulator is placed between the cooling coil and the compressor to capture unused liquid refrigerant and ensures that only vapor enters the compressor. The compression process increases the pressure of the refrigerant vapor and significantly increases the temperature of the vapor. The compressor pumps the vapor through another heat exchanger (outdoor condenser) where heat is rejected and the hot gas is condensed to a warm high pressure liquid. This warm high pressure liquid is pumped through a smaller copper tube (liquid line) to a filter (or filter/dryer) and then on to an expansion device where the high pressure liquid is reduced to a cold, low pressure liquid. The cold liquid enters the indoor cooling coil and the process repeats.
Need your air conditioning repaired today? Let Dunes Heating and Air Conditioning LLC.  same-day air conditioning repair service come to the rescue. Our air conditioning repair, maintenance and installation technicians and contractors are some of the most highly skilled AC repair technicians in the area. So whether you need your commercial air conditioner repaired or your home air conditioning system replaced, let our team of factory trained and certified home central air conditioning repair technicians be there for you and your family!
At Heating Repair Moorpark, we also have the added benefit of being capable to deliver top notch emergency services to any of our Moorpark area customers that are in need of it. If you have a sudden malfunction that needs to be dealt with easily, such as a automatic garage door or gate opener concern that would avoid you from going to work, as well as if your home becomes destroyed because of the weather, our emergency support experts are outfitted to take care of your needs.
Fuses -- Anyone who has worked with electrical systems knows all about fuses and how they fail. They can burn out over time, may just be loose, or can blow out during an electrical storm or due to overload from another failed component. Of course, that's what they're supposed to do; they stop surges from going through and damaging the rest of the system. When a fuse fails, whatever system it was protecting will stop working.

We maintain a complaint-free A+ rating with the Better Business Bureau, and are a 2017 Better Business Award Winner for ethics. Comfort Plus Services has achieved recognition as a Carrier Factory Authorized Dealer for sound business practices, technical expertise, and customer approval ratings. We simplify the demands of local weather and a comfortable home with upfront pricing, honest estimates, comprehensive service plans, and Emergency Service throughout Salisbury, Fruitland, Delmar, Hebron, Eden, Delmar, Parsonsburg, Pittsville, Mardela Springs, Princess Anne & Willards, MD and more. See our Areas of Service. For new home comfort systems, Comfort Plus Services protects your interests with a 100% money back guarantee. We provide expert service you can trust.
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.
If you’re looking for a professional heating company in Denver with the proper experience to handle your project, our crew has many years of training and experience on most major heating systems available in the Denver area. Our heating company in Denver understands that in some situations, the scope of the damage may put the units beyond repair. In this instance, we can offer you help finding the right energy efficient model that will provide you warmth and savings in your wallet. Heating in Denver can be expensive during the coldest time of year, so choosing the right heating system can give the same amount of heat while at the same time providing big savings when our Denver heater repair technicians help you pick the right system for your home.
How Do You Know When You Need Air Conditioner Repair in Dallas / Fort Worth? Several things can impede the proper function of your air conditioning system. The accumulation of caked on grime and dirt on the condenser coil located outside can force the system to work harder and waste energy. A leak in the coils can result in insufficient refrigerant in the system. Other common culprits for malfunctioning air conditioning systems include a clogged A/C drain and faulty electric controls or sensors. The service professionals at Baker Brothers Plumbing & Air Conditioning will use the latest technology and tools to diagnose your air conditioning system’s problem and correct it quickly and cost-effectively. Our technicians will arrive at your home with fully stocked trucks with the tools and equipment they need to complete almost all jobs within one visit.
Replacing a capacitor is easy. Just take a photo of the wires before disconnecting anything (you may need a reference later on). Then discharge the stored energy in the old capacitor (Photo 4). Use needle-nose pliers to pluck one wire at a time from the old capacitor and snap it onto the corresponding tab of the new capacitor. The female crimp connectors should snap tightly onto the capacitor tabs. Wiggle each connector to see if it’s tight. If it’s not, remove the connector and bend the rounded edges of it so it makes a tighter fit on the tab. When you’ve swapped all the wires, secure the new capacitor (Photo 5).
Mitsubishi Electric is a world leader in air conditioning systems for residential, commercial and industrial use. Challenged to create air conditioning systems that provide exemplary performance in the wide-ranging climatic conditions found throughout Japan, our engineers develop amazingly sophisticated yet durable units and systems capable of constant use under virtually any natural climatic condition on earth.
As a Carrier® dealer, with a wide variety of products to choose from, we can keep your family healthy and feeling comfortable all year long. We carry a complete line of indoor comfort equipment with innovations that raise the standards of comfort and reliability, including air conditioners, heat pumps, gas furnaces, programmable thermostats, humidifiers, ductless split systems, geothermal systems, boilers, air cleaners, ultra violet lights, ventilators and zoning products. Let the experts at Dunes Heating and Air Conditioning, LLC help you customize a solution that's right for you.
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.
A reliable, efficient, and modern cooling system makes everyday life a whole lot better.  Whether you’re in need of new installation, equipment replacement, seasonal maintenance, or repair in Chicagoland and the surrounding suburbs, Air Blue Heating and Cooling Inc. is the right answer.  We bring you quality products and services that result in pure luxury without painful costs.  As a Carrier Factory Authorized Dealer, we specialize in the most recognized, award-winning, and innovative air conditioners on the market.  Along with precision temperature control, take advantage of unprecedented energy efficiency, whisper-quiet sound levels, and a range of features that enable greater control over your environment.  Our team is fully licensed, bonded, insured, and NATE-certified.  We make it easy to get the expert help you need with same-day service/installation, and 24/7 Emergency Service across Wheeling, Buffalo Grove, Northbrook, Deerfield, IL.  When you contact Air Blue Heating and Cooling Inc., we don’t waste your time or money, leave behind mess or damage, or consider our job done until you are 100% satisfied.  With over thirty years of practical experience, we are your local solution to perfect comfort.
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%.
First off, HVAC stands for “Heating, Ventilation, and Air Conditioning,” while AC stands for just the last part: “Air Conditioning.” In other words, when we talk about AC, we’re generally talking about the system that cools the air in your home (although sometimes people do use the term AC to refer to units that provide heat as well, especially when they’re talking about heat pumps). However, when we talk about HVAC, we could be talking about a system that does either the heating or the cooling, or both.
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).
As the system carries the cool air through the home, it becomes warmer as it travels through the system.  The air then circulates back to the central air conditioner through the return ducts and registers.  A benefit of a central air conditioner is that it helps dehumidify the incoming air but with extreme humidity, you may have to invest in a dehumidifier to help lower the moisture in the air.  There are also two different types of central air conditioners to choose from.
As one of the premier heating & cooling companies in St. Louis, Vogel has dedicated our business to serving our customers with the utmost quality in HVAC services for both residential and commercial entities alike. We strive to build out a culture within our team that delivers the kind of experience you deserve when working with a service provider. The qualities that are most important to you, are most important to us - convenience, trustworthiness, good value, impeccable quality, and our willingness to stand behind our successes and learn from our mistakes. We invite you to explore our site, see what customers say, and give us a call.
Wiring up the thermostat is usually pretty straightforward if an old one is being replaced. If a thermostat is being put in where one had never been before, that could involve running new wiring. The placement of the thermostat is also important so that its sensors can get an accurate reading of the temperature. A thermostat that is blocked by a bookcase or other large furniture will not get a good reading and will not perform efficiently.
When your gas furnace isn’t blowing hot air, the issue could be due to a faulty pilot light or broken ignitor. Remove the furnace cover panel and visually inspect whether you can see a flame from the pilot light. A natural gas furnace will be blue and yellow in color, and a propane furnace should have a bluish green flame with a yellow tip. If you can see a flame and it appears normal, the issue could be related to the furnace blower motor or other complex furnace parts. If the flame appears low or non-existent, it’s best to contact an experienced furnace repair company. Remember to never touch any open wires; contact a professional.

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.
Over the Labor Day weekend our hot water heater decided it was time to say good bye. Since we had our fall check the week before, we called Nerthlings. I cannot say enough good things about how this situation was handled. The technician, Dwain, was knowledgeable, friendly, and quite helpful without being pushy. Our questions were answered clearly. I am never made to feel that this is something...

If the condenser coils are clogged, the compressor can overheat and shut down. You’ll experience intermittent periods of minimal cooling, followed by no cooling. Even if you’re “sure” the condenser coils are clean, clean them again. Turn off the power. Flip the air conditioning service and furnace circuit breakers in your main electrical panel to the “Off” position. Next, turn off the power switch right at the furnace or air handler. Then yank the disconnect block (Photo 1) and clean the condenser coils (Photo 2). If the air conditioning service still doesn’t work properly after you’ve cleaned the condenser coils, installed a new filter and opened all the supply vents, proceed with the following repairs.


Humidity is becoming more of a concern to building operators and owners. High indoor humidity leads to mold and mildew growth inside the building. The are several methods of controlling indoor humidity. The simplest (and most expensive) method is to connect a humidistat to an electric heater. When the humidity inside the building rises above the humidistat set point, the heater is turned on. The additional heat causes the air conditioning system to run longer and remove more moisture.
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