Some systems include an "economizer mode", which is sometimes called a "free-cooling mode". When economizing, the control system will open (fully or partially) the outside air damper and close (fully or partially) the return air damper. This will cause fresh, outside air to be supplied to the system. When the outside air is cooler than the demanded cool air, this will allow the demand to be met without using the mechanical supply of cooling (typically chilled water or a direct expansion "DX" unit), thus saving energy. The control system can compare the temperature of the outside air vs. return air, or it can compare the enthalpy of the air, as is frequently done in climates where humidity is more of an issue. In both cases, the outside air must be less energetic than the return air for the system to enter the economizer mode.
In 1758, Benjamin Franklin and John Hadley, a chemistry professor at Cambridge University, conducted an experiment to explore the principle of evaporation as a means to rapidly cool an object. Franklin and Hadley confirmed that evaporation of highly volatile liquids (such as alcohol and ether) could be used to drive down the temperature of an object past the freezing point of water. They conducted their experiment with the bulb of a mercury thermometer as their object and with a bellows used to speed up the evaporation. They lowered the temperature of the thermometer bulb down to −14 °C (7 °F) while the ambient temperature was 18 °C (64 °F). Franklin noted that, soon after they passed the freezing point of water 0 °C (32 °F), a thin film of ice formed on the surface of the thermometer's bulb and that the ice mass was about 6 mm (1⁄4 in) thick when they stopped the experiment upon reaching −14 °C (7 °F). Franklin concluded: "From this experiment one may see the possibility of freezing a man to death on a warm summer's day."[9]
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.
Extreme’s One Hour Heating & Air Conditioning in Dayton, Ohio is a premier HVAC repair and replacement service provider. We take pride with our industry best “on-time guarantee”.  There is no reason to wait around at home for the technician to arrive, Extreme’s One Hour Heating and air Conditioning gives you convenient scheduling options and we will be there on time!  Never wait at home on us to arrive. We offer ½ hour call or text ahead to let you know the technician is on the way.  Call us now  937.426.7399

Our skilled technicians arrive prepared to handle the scope of even complex malfunctions, with all makes and models of heating and cooling equipment, most often resolving the problem on the spot.  For all your HVAC service, repairs, and installations in Livermore, CA, Pleasanton, CA & Dublin, CA, call the team from Miller’s Air Conditioning & Heating!


At Horizon Services, we strive to provide all of our customers with the peace of mind that comes from knowing that you have a skilled team on-call for any AC emergencies that may arise. We have more than 300 fully stocked trucks ready to go at a moment's notice. Our Horizon technicians undergo rigorous training, including a mandatory 150 hours of training every year, to ensure that they're always up to date on the latest techniques and HVAC technology. Plus, we perform extensive background checks, including drug and criminal checks, on all of our employees so you don't have to worry about letting a stranger into your home when your AC breaks down in the middle of the night. When you're dealing with an air conditioning emergency, trust the experts at Horizon Services!
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.
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