Celebrate Air Conditioning Appreciation Week with this gallery  from Magnum Photos. Ever wonder about the water that drips down from air conditioners as an unwelcome sidewalk surprise when you’re walking to work? In 2011, Forrest Wickman looked into the reason why ACs are so leaky, and if there’s anything unsanitary about the water that’s dripping down on you. The original article is reprinted below. Walk down any city sidewalk on a hot summer day, and you're bound to get wet—and not just when it's raining. Water drips from window AC units, especially on muggy days, and this unpleasant drizzle can fall into your hair or even onto the lip of your morning coffee cup. Is all that dripping water sanitary? Yes, as a general rule. Most of the dripping from air conditioners is just condensed water vapor that comes from the air inside the building. Window air conditioners are designed to drain this water from the back, raining it down on any unsuspecting pedestrians below.

In most ways this water is exactly like rain (which also forms from condensed water vapor) or the moisture that collects on a cool can of soda, and it's typically no more harmful. However, in rare cases small amounts of water can be left to stagnate inside the air conditioner, making it a breeding ground for bacteria. On a hot and humid day, a window unit can drip up to 2 gallons of water, which accumulates on its evaporator coil as it cools and dehumidifies the air. (Very little condensation gathers on the exterior side of an AC, which tends to be warmer than the air around it.) This coil, like many plumbing pipes used for drinking water, is made of copper (which is also what makes air conditioners so heavy), and it's much cleaner than you might expect from looking at a dusty AC filter. While copper can be unhealthy in high doses, the condensate from air conditioners seems to be low in minerals and dissolved solids. In a properly functioning air conditioner, the water drips down from the coil into a condensate pan and then exits the unit through a drain or tube.

However, a clog in this drain or tube can leave a puddle to accumulate inside, which is an ideal environment for many types of harmful bacteria. In particular, a 1976 outbreak of Legionnaires' disease was caused by bacteria that spread out of the air conditioning system at Philadelphia's Bellevue-Stratford Hotel. window ac unit not cooling enough(That's how the disease got its name: Many of the victims were attending an American Legion convention.) outdoor ac unit not working onWhile Legionella is known to thrive in the cooling towers of large air conditioning systems like the one at that Philadelphia hotel, it does not seem to grow in smaller units. 3 ton package unitFurthermore, dripping water isn't really stagnant, so it's extremely unlikely that the water raining down on pedestrians would be infected.

The water that drips from air conditioners is probably even safe for drinking. (It's certainly more potable than the drinking water in many countries.) Still, for the reasons mentioned above, it's best not to tilt your head back for a draft. If you're looking for a better use for your air conditioner's condensate, the Explainer recommends using it to water your plants. Got a question about today's news? Explainer thanks Douglas T. Reindl of the University of Wisconsin-Madison and Mark Sobsey of the University of North Carolina at Chapel Hill.A small, portable generator can power a window AC unit if it has the right wattage rating. Any window air conditioning unit can be powered by a generator. However, you may not be able to power many other appliances plus an AC window unit, depending on the size of the generator. Wattage is the primary unit of measurement used to determine how much a generator can handle. If you are considering purchasing a generator to power a window AC unit and additional appliances, you need to do basic math and planning to determine if the generator you choose is sufficient.

Wattage Wattage (W) is the basic unit of measurement for electric power. It is defined as amperage (current or electrical flow) multiplied by voltage (electric potential). All appliances that plug into a standard duplex receptacle in the United States operate on a nominal 120 volts (V). The actual volts present at the outlet depends on a number of factors, including the electrical utility, and the length and size of the cable feeding the outlet. However, you can reasonably expect that a properly installed duplex receptacle on a 120-V circuit has between 110 and 125 volts present. Amperage (A) varies from unit to unit. Typical Window Unit Wattage Window AC units have two watt ratings: starting wattage and running wattage. Starting wattage is higher because as the machine starts up and the motor begins to turn, amperage spikes as the motor draws higher current to overcome inertia and starting friction. A typical starting wattage for a window unit is 2200. Once the motor is running steadily, the amperage drops and the wattage usually is around 1500.

Your unit may have different ratings. Examine the nameplate or the specifications in the manual to determine how much power your AC unit uses. Generators There are generators for just about any situation. The smallest generators are portable gas-powered units. The largest industrial-size generators can power a whole facility. A homeowner is likely to have either a small, portable generator or a whole-house generator. Electricians generally install a generator, which is wired to a sub-panel or the main panel, depending on its size and specifications. Connecting your generator to an electrical panel allows for more efficient and safer power distribution throughout a house. Generator Wattage Generators are rated according to the maximum wattage they can handle. A typical portable generator for emergency use by a homeowner might be rated 4000 to 7500 W. Whole-house standby models typically are rated 25,000 W or higher. If you are considering purchasing a generator, deciding what size to buy is not as simple as adding up the watts of the appliances you'll use.