There is a lot to think about when you’re renovating a home. You need to make many decisions, starting with what contractor to use and how much money you want to spend. It helps if you have a clear vision for how you want your home to look when you’re done. If you’re not sure what it is that you want yet, take some time to look through my blog. I’ll discuss everything from home additions to flooring materials to appliances and fixtures. These articles will help you get a sense of the possibilities for your home renovation, and help you narrow down your options. Eventually, you’ll decide on the renovations that are right for you.
Most homes that were built in the 1950s did not have central air conditioning. Although Willis Carrier invented modern-day air conditioning in 1902, Slate records that only 10 percent of American homes had it by 1965. Units have since been installed in many of these pre-1965 homes. Some 1950s homes still do not have central air conditioning, though. If you own one of these homes, be sure its electrical system can safely handle the demands of a central air conditioning unit before installing one. You may need to a breaker panel upgrade.
Electric Demands in the 1950s and Today
In general, today's breaker panels can handle a heavier load than those used in the 1950s. Darrell Boyd, a licensed electrician, writes that kitchen today often use as much power as an entire home did in the 1950s or 1960s. Thus, the breaker panels installed by electricians today need higher capacities than those used a half-century ago.
Boyd recommends using at least a 200-amp breaker panel in homes today. These have more than three times the capacity of 60-amp panels, which Home Depot notes were common in older homes. Currently, 60-, 100- and 200-amp breaker panels are widely available.
The Demands of an Air Conditioner
Some older home's circuit breakers have been upgraded to heavier duty ones, but many have not. An electrician can tell you whether your home's has been. If it hasn't been upgraded, then running an air conditioner's 220-volt line from it might not be safe.
Lazar Rozenblat has a chart that shows how many amps a central air conditioner needs to start up. He explains that air conditioners use lots of power to start up but draw significantly less electricity once running. The amps required to start a unit are expressed as locked rotor amps (LR amps), and your breaker will need to be able to meet the LRA demands of your new air conditioner. According to his chart, a:
Even if you're a small, 1-ton unit uses more than half of the capacity of older 60-amp breakers. If anything else is drawing electricity when the air conditioner kicks in, the circuit may become overloaded. An overloaded circuit provides an inconsistent flow of electricity, which can cause lights to dim and burn out your air conditioner's motor.
In the southeast United States, a 1-ton air conditioner is only suited for a 600 to 900 square foot home, though. As Ebay's chart shows, you will likely need a larger unit no matter where in the country you reside. A 2- or 3-ton air conditioner requires more power than a 60-amp circuit breaker can handle, and it could even max out a 100-amp panel if other appliances are running.
Upgrade Your Breaker Panel
The safest choice is to upgrade your breaker panel before you install your home's first air conditioner. Going from a 60- or 100-amp panel to a 200-amp one will ensure that it can safely meet your home's electricity needs, even when your new air conditioner is turning on.
Before you pay for a new air conditioner, consult with a local electrician so that you understand how the unit will impact your home's electrical system. A licensed electrician from a site like http://attaboyservices.com/ will be able to help you identify your current panel's capacity and compare that with the air conditioner's draw. Your home will likely need a new panel if it was built in the 1950s, before air conditioning was widely used in residences. Your electrician will be able to upgrade it for you.