It's the first hot day of the summer. Uncomfortably shifting in your seat, you turn on that long-neglected AC knob, only to discover an unwelcome blast of warm air streaming out from the vents. A bad situation made worse: that's when you turn to us—your air conditioning service and repair headquarters. Did you know that without regular maintenance an air conditioner loses about 5% of its original efficiency per year? This means that without proper maintenance, your air conditioning unit may be performing as poorly as other models that are years older! But there is good news: you can still recover most of that lost efficiency. Schedule an appointment with one of our factory-trained professionals—we understand all aspects of AC repair, from modern computerized components to environmental disposal concerns. Today's AC systems are fairly complex, and new improvements are always being initiated. That's why you need to turn to us, the qualified source for everything related to your air conditioning system. The following is a brief schematic of some of the basic components that comprise this system:
• The evaporator is designed to remove heat from the inside of your vehicle; therefore it's a heat exchanger that's vital to your vehicle's AC system (not to mention your comfort). The evaporator allows the refrigerant to absorb heat, causing it to boil and change into a vapor. When this occurs, the vapor is removed from the evaporator by the compressor, cooling your car and reducing humidity. Because the evaporator houses the most refrigerant in this heat transfer process, it is the most susceptible to corrosion by harmful acids. Usually this damages the evaporator beyond repair, which is why it's imperative you see us to prevent this from happening.
• The compressor is a belt-driven device that derives its name from compressing refrigerant gas and transferring it into the condenser. While basically acting as a simple pump, the compressor is the core of your vehicle's air conditioning system.
• The condenser's primary function is to cool the refrigerant. It is a heat dissipating apparatus that radiates heat released by compressed gases and condenses them into high pressure liquids. The location of your condenser depends on how new your car is, but typically it's found at the front of the vehicle, directly in front of the engine cooling radiator.
Orifice tube/expansion valve:
• The orifice tube (also known as the expansion valve) is a controlling mechanism that regulates the flow of refrigerant throughout the system. In addition to this, it also converts high pressure liquid refrigerant (from the condenser) into a low pressure liquid, so that it can enter the evaporator. Generally located at the evaporator inlet, the orifice tube could also be found between the condenser and the evaporator, or in the outlet of the condenser.
• The receiver is a metal container that serves as a storage receptacle for the refrigerant. It's also referred to as a drier because it absorbs moisture from the refrigerant and filters out particles of debris and harmful acids that would otherwise harm your AC system. Commonly located on the liquid line of the AC system, you should change your drier every 3-4 years to insure quality filtration and prevent any damage caused by these detrimental chemicals.
An alternator is a generator of electric power in you car and is a major component of your vehicle's charging system. Whenever your engine is running, the alternator charges your battery and supplies additional electric power for the vehicle's electrical systems. An alternator is attached to the engine and is driven by a drive belt (also known as a serpentine belt).
An alternator is a maintenance-free unit. On average, an alternator can last for 8-12 years without any repairs. If an alternator fails, the car may still run on battery power alone for a while, but will die as soon as the battery charge is depleted. Replacing an alternator with a new unit is quite expensive, but there are alternatives.
The most frequent symptom of a problem with your vehicle's charging system is a battery-shaped warning light (in the photo) or the "CHARGE" icon that comes on while driving. Normally this warning light should come on when you turn the ignition, but should disappears as soon as the engine is started. If it stays on, there is a problem with your charging system. The charging system warning light doesn't point directly to a failed alternator, although alternator problems are very common. You mechanic will need to do further testing to pinpoint the defective part.
Sometimes when the alternator becomes weak, you may notice that your car's headlights and dash lights become dim at idle, but get brighter at higher RPMs.
Your mechanic can test the state of your charging system with the battery and charging system tester (in the photo). A battery and charging system test (AVR test) can cost from $30 to $50. The test can show if the charging system is weak or not working at all. It also can detect if one of the diodes inside the alternator has failed. If the charging system failed the test, your mechanic
will need to do further diagnostic to see if it's the alternator or something else causing the problem. Other charging system problems include a loose drive belt, faulty wiring or blown fuse, defective ignition switch, etc.
If no charging system tester is available, your mechanic can do a simple voltage test. The test involves checking the battery voltage with the engine off and with the engine running. The battery voltage should increase once the engine is started, as the alternator supplies additional power (see the photo). If the battery voltage does not increase once the engine is started, there is a problem with the charging system.
A typical AC car alternator has two windings: a stator (stationary outside winding) and a rotor (rotating inner winding). A voltage supplied through the voltage regulator to the rotor winding energizes the rotor and turns it into a magnet. The rotor is rotated by the engine via a drive belt. The magnetic field produced by the rotating rotor induces AC electric current in the stationary stator winding. Diodes are used to convert AC current into DC current used in the vehicle's electric system. The output voltage is controlled by the voltage regulator (photo below). Typically, a voltage regulator is built-in into the alternator.
The most common alternator problems include worn carbon brushes (the two "legs" in this photo), worn contact rings (the two copper cylinders at the back of the rotor in the cutaway image) and a failed voltage regulator.
Bad outer and inner alternator bearings (large and small silver cylinders in the cutaway image above) can produce a whining noise. When the alternator is rebuilt, the bearings, voltage regulator, brushes and some other parts are typically replaced with new ones.
Often an alternator can fail prematurely when a protective engine undercover or shield is damaged or missing. This is happens because sand and water from the road can get inside the alternator and cause it to wear faster. If your engine undershield is damaged, have it replaced to keep the engine compartment clean and dry. A coolant or oil leak can also damage the alternator. Similarly, if you have to shampoo the engine compartment, the alternator must be protected from water and detergent.
Replacing an alternator could be costly: $420 or higher depending on the car and what part is used. An aftermarket or rebuilt alternator is usually less expensive than an OEM part bought from a dealer. One of the cheaper alternatives is to have your own alternator rebuilt. The way it works is your mechanic can remove the alternator and send it to the nearest alternator/starter rebuilder shop. Once the alternator is rebuilt, your mechanic will install it back. It may take more time, may have a cheaper cost.