Demand controlled kitchen ventilation (DCKV) is a building controls approach of slowing down kitchen exhaust fans and subsequent supply air in response to the actual cooking loads in a commercial kitchen. Traditional commercial kitchen ventilation systems operate at 100% fan speed independent of the volume of cooking activity and DCKV technology changes that to provide significant fan energy and conditioned air savings. By deploying smart sensing technology, both the exhaust and supply fans can be controlled to capitalize on the Law of Affinity for motor energy savings, reduce makeup air heating and cooling energy, increasing safety and reducing ambient kitchen noise levels.[27]

The selection of the working fluids (refrigerants) has a significant impact not only on the performance of the air conditioners but on the environment as well. Most refrigerants used for air conditioning contribute to global warming, and many also deplete the ozone layer.[59] CFCs, HCFCs, and HFCs are potent greenhouse gases when leaked to the atmosphere.


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.
A little simple math can help determine the size system you need. A rule of thumb is 20 BTUs per square foot. So, a 500 square foot room would need 10,000 BTUs to cool or warm it efficiently. This assumes that you live in a temperate region and have adequate insulation with no energy loss. In the real world, all units have some degree of energy loss. This is reflected in an HVAC system's SEER rating for cooling and AFUE rating for heating.
Window unit air conditioners are installed in an open window. The interior air is cooled as a fan blows it over the evaporator. On the exterior the heat drawn from the interior is dissipated into the environment as a second fan blows outside air over the condenser. A large house or building may have several such units, allowing each room to be cooled separately.

Sky Heating & Air Conditioning provides a wide range of quality HVAC services to homeowners across Portland and The Dalles.  By bringing together skilled technicians and premier products, we deliver superior value for your investment.  We utilize tried and true strategies to enhance efficiency, comfort, and convenience throughout your home.  For heating and air conditioning installation, repair, and regular maintenance, no one takes better care of you than Sky Heating & Air Conditioning.  And we’re always here!  Count on us 24 hours a day, 7 days a week, to protect your safety, comfort, and best interests.
Indoor Fan Motor -- Indoor fans circulate the air from your house and through the system. Age and dust buildup are the two biggest contributing factors to their failure. When they are starting to fail they will often make noise. Failure of the fan will result in no heating or cooling, and if it is not repaired soon, it can cause other components to fail.

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.


Many things can go wrong with your furnace, all of which should be repaired and examined by experienced professionals. Trust Randazzo Heating, Cooling, and Fireplaces to repair and help you maintain your furnace*. We value our customers and their decisions, so we will always be honest and explain the best possible solution for you. Contact us today so we can help you out! Click Here for our warranty policy.
Since the 1980s, manufacturers of HVAC equipment have been making an effort to make the systems they manufacture more efficient. This was originally driven by rising energy costs, and has more recently been driven by increased awareness of environmental issues. Additionally, improvements to the HVAC system efficiency can also help increase occupant health and productivity.[21] In the US, the EPA has imposed tighter restrictions over the years. There are several methods for making HVAC systems more efficient.
Air Handling Unit (AHU): a device used to condition and circulate air as part of a heating, ventilating, and air-conditioning (HVAC) system. An air handler is usually a large metal box containing a blower, heating or cooling elements, filter racks or chambers, sound attenuators, and dampers. Air handlers usually connect to a ductwork ventilation system that distributes the conditioned air through the building and returns it to the AHU.
A hot aisle is a layout design for server racks and other computing equipment in a data centre. Hot aisle data centre design involves lining up server racks in alternating rows with cold air intakes facing one way and hot air exhausts facing the other. The rows the heated exhausts pour into are called hot aisles. See Data Centre Aisle Containment for more information. 

This is probably the most common question we hear. To give an accurate price, we need to get a safety certified technician out to your home in a fully stocked truck to take a look at your particular situation. Our technician will give you a precise price with your options BEFORE any work begins. Each of our technicians are well trained, experienced, drug tested and background checked so that you can rest easy knowing your services will be performed in a timely and professional manner. If you need help paying for your services, we even offer financing with approved credit through Wells Fargo. Click here to learn more about our financing services.
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.
Most of the air conditioners in residential buildings are in the form of split systems – only bigger. They have a cooling fan, a condenser coil and a compressor housed in a separate condensing unit. The evaporator coil is usually inside an air handler (indoor) unit normally installed on the furnace. When the furnace is electric, a blower is included in the system.
Air conditioner equipment power in the U.S. is often described in terms of "tons of refrigeration", with each approximately equal to the cooling power of one short ton (2000 pounds or 907 kilograms) of ice melting in a 24-hour period. The value is defined as 12,000 BTU per hour, or 3517 watts.[32] Residential central air systems are usually from 1 to 5 tons (3.5 to 18 kW) in capacity.
Since 1971, One Hour Heating & Air Conditioning has been the leading Charlotte AC repair company. Our technicians are not only professional experts, but they work 24/7, 365 days a year to make sure you’re comfortable. Plus, they’re “Always on time… or you don’t pay a dime.” ®. If you are looking for heating and air in Charlotte NC, you are in the right place!
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).

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.


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.
Most of the air conditioners in residential buildings are in the form of split systems – only bigger. They have a cooling fan, a condenser coil and a compressor housed in a separate condensing unit. The evaporator coil is usually inside an air handler (indoor) unit normally installed on the furnace. When the furnace is electric, a blower is included in the system.
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.
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