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]

When your home or workplace is too hot or too cold, no one is happy. We have the expertise to solve any temperature problems you may have. We also realize that temperature isn’t the only factor in comfort: ventilation, indoor air quality, and automation also play a role in making your indoor environment a haven for your family, customers and employees.
The summers here in Alexandria can range from almost pleasant to downright brutal. And you know as well as we do that it’s those latter days when your central AC or heat pump will decide to go down! But you don’t have to seek solace at the Waterfront or over at Cameron Run Regional Park. The secret to restoring your comfort lies with the certified specialists at HVAC & Plumbing Unlimited!
If a heat exchanger cracks or contains holes, leaks can release carbon monoxide into your home. Carbon monoxide is nearly impossible for humans to detect on their own due to its characteristics of being colorless and odorless. Because of this, it is referred to as “The Silent Killer”. Some symptoms of carbon monoxide poisoning include headache, dizziness, fatigue, nausea and vomiting. It is extremely important to have a HVAC technician perform a furnace inspection annually to prevent problems such as carbon monoxide poisoning. UGI Heating, Cooling & Plumbing offers yearly maintenance packages and service agreements that include yearly maintenance and furnace inspections.
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