Today's topic is: How to buy a used car without getting screwed. It's brought to you by your old pal Doug DeMuro, noted Jalopnik columnist, who once purchased a BMW M3 from a shady used car dealer whose sales manager insisted that I make out the check to him personally. More specifically, I've decided to devote this column to a phrase you hear a lot when you're looking for a used car. That phrase is: "the air conditioning just needs a charge." Private sellers say this. Craigslist ads say this. This phrase has become so common that you get the sense, as a used car shopper, that there are just rows of used cars, dozens of used cars, sitting out there with their air conditioning depleted, drained, ready to be plugged in and charged up like an iPhone.Well, ladies and gentlemen, I'm here to tell you: it's all bullshit. To explain what I mean, allow me to teach you how air conditioning works. I'm able to do this because I am an expert in the field, in the sense that I have personally used air conditioning for approximately 26 years, and I can immediately detect when I am in a place that lacks air conditioning, such as the outdoors.

Anyway, as I understand it, here's how it works: there are several vents in your automobile, and possibly your home, that are hooked up to air conditioning ducts. If you were able to shrink down to a small size, like a thumbtack with legs, you would be able to follow these ducts to something that we in the HVAC community refer to as the "air conditioning unit." ac unit for sale usedI know this is highly technical writing, but please follow along, because there will be a quiz later.large room ac unitNow, the air conditioning unit includes three necessary components in order to work properly. ac window unit for small windowNumber two: a magical component called the "compressor." And number three, copper wire. We know this because thieves are always stealing copper wire from air conditioners in places like Mississippi, and then they get electrocuted, which is very sad for the homeowner because he is unable to fix his air conditioning until the coroner removes the body.

Now, here's where the "needs a charge" thing comes in. When your air conditioner stops working, the problem can most likely be traced one of four distinct possibilities. One: the compressor isn't working. Two: there's a leak somewhere in the system. Three: it needs more refrigerant. And four: a thief died while stealing your copper wire, and is currently being slowly consumed by wild rodents.More often than not, the problem lies somewhere deep within the air conditioner, where some key part has failed. This is usually an expensive part with some fancy name, such as the adapter tube restrictor mount, and in order to get to it they have to remove your dashboard, and your steering wheel, and your gauge cluster, and also slap you in the face with a surge protector. But I admit that occasionally the reason the air conditioning isn't working is that the car simply lacks refrigerant. This is what people are talking about when they tell you the air conditioner "needs a charge." You remove some stuff under the hood, you open up the refrigerant tub, you pour in the refrigerant, and BAM!

Good as new, fully recharged, ready to blow cold air in your face for years to come. Only there's a problem: adding refrigerant takes approximately four seconds. Dealers charge you $100 for the job, and the majority of that cost is the refrigerant itself. So you gotta wonder: if a car is sitting at a dealership, which includes a service department, and the air conditioning simply "needs a charge"… WHY DON'T THEY JUST CHARGE IT?The answer is: because the air conditioning doesn't need a charge. This is just a simple explanation that idiot salespeople tell idiot customers who desperately seek reassurance. In reality, the air conditioning needs that restrictor mount, so we're going to have to start tearing down the dashboard, and can you please pick out a surge protector we can slap you with? In other words: "air conditioning needs a charge" is the modern-day equivalent of "owned by a little old lady who only drove it to church on Sundays."There is, however, a huge benefit when a seller tells you the "air conditioning needs a charge."

And that is: you now have the advantage of knowing that you can't trust anything he says. With some sellers, you think you can trust them, and you assume you can trust them, and you're feeling that maybe you can trust them, and then it turns out that the timing belt is actually a piece of looseleaf notebook paper. But the second "air conditioning needs a charge" comes out of the seller's mouth, BOOM! This guy's lying to me, and now I no longer have to believe anything he says.I'll give you an example. As many of you know, I'm currently mired in the search for a used automobile to buy for the purposes of writing, and Tweeting, and creating low-budget YouTube videos with a microphone the size of a stapler. So a couple weeks ago, I find a nice car on Long Island, and I'm talking to the seller, and I'm thinking I'll just go ahead and buy it, sight-unseen, no inspection needed. And then I decide to casually ask about the air conditioning. It just needs a charge." Needless to say, the car is now going in for a full pre-purchase inspection next week at a trusted mechanic.

Fortunately, he didn't try to tell me the car was owned by a little old lady who only drove it to church on Sundays. Then I would've slapped him with a surge protector.@DougDeMuro is the author of Plays With Cars. He owned an E63 AMG wagon and once tried to evade police at the Tail of the Dragon using a pontoon boat. He worked as a manager for Porsche Cars North America before quitting to become a writer, largely because it meant he no longer had to wear pants. Also, he wrote this entire bio himself in the third person.Unfortunately, there will come a time when even the most properly maintained furnace or air conditioner can go on no longer. According to a recent American Home Comfort Study, the lifespans of different equipment tend to hover around the same marks. maintained and installed furnace can last 20 years while an air conditioner and heat pump can last around 16 years and 14 years, respectively (on average). imagine, heating and cooling technology progresses immensely over such a long period

Here are some reasons why you should replace your old HVAC system if it is approaching the end of its lifespan. Old systems most likely use R-22, an ozone-depleting refrigerant that was recently named harmful for the environment. Manufacturers are slowly phasing-out the use of R-22 and creating units that are compatible with R-410A. Initially R-410A was more expensive than R-22 but that gap has closed. Switch to R-410A now and save later. Replacing your old unit with a new unit will result in greater home comfort throughoutIt’s not that your old unit wasn’t originally a quality system at its time, but it is just that newer systems have surpassed the technology that was available when your old unit was produced. indoor air quality features that can help you reduce allergens, volatile organic compounds and other indoor air contaminants so that you canThis is all available, plus you can potentially save bundles of money on your monthly utility bills when compared to the costs of operating your old unit.

Old units may get, for lack of a better word, clunky as they age. All of those years of hard work and exposure to either outdoor elements or poorly insulated interior spaces (i.e. basements, attics and crawlspaces) can take their toll on even the highest-qualityWhile regular preventative maintenance might help stave off the effects of the elements on your unit, eventually it may start becoming loud while it operates. system will not have those problems because they are, of course, brand new and contain additional system features that can help reduce noise. Our iQ Drive air conditioners and heat pumps are some of the quietest systems in the industry – down to 59 decibels. minimum efficiency air conditioner or furnace can be a significant jumpThe old furnace in your basement may only be originally rated at 60% toIn order to comply with national regulations, furnaces manufactured today have to be rated at a minimum of 80% AFUE. This is a 10% to 20% increase in efficiency, and

we are not even taking into account that your old furnace may have even become less efficientThe same goes for air conditioners. Old efficiency requirements were setNowadays, air conditioners must be at least 13 SEER. That is a 30% increase in efficiency just by switching to a minimum efficiency system. that reach the pinnacle of HVAC system efficiency – the 25.5-SEER iQ Drive® air conditioner 97% AFUE iQ Drive modulating gas furnace. Think of the energy savings you will see when you replace an old air conditioner or furnace with one of these Frigidaire air conditioner, heat pumps and furnaces are all covered by an outstanding 10-Year Limited All Parts Warranty when the unit is registered. talk to your local HVAC system replacement contractor. If you are looking for an HVAC professional in your area, turn to the Frigidaire dealer locator.Use our system selection tool. Answer a few questions about your needs and we'll suggest several options.