| Most of us have become accustomed to the | | | | Evaporator |
| comfort provided by our vehicles' heating and air | | | | Your air conditioner's evaporator has a few |
| conditioning system. During the cold months, | | | | responsibilities. First, it is tasked with removing |
| warm air keeps the chill at bay. During the | | | | heat from within the cabin of your car. Second, it |
| warmer months, the A/C produces cool air to | | | | removes moisture from the air that leaves it and |
| make the driving experience more comfortable. | | | | passes through the vents. |
| Like most auto parts and systems, the heater | | | | By the time the liquid refrigerant arrives from the |
| and air conditioner work without our thinking | | | | expansion valve, much of its pressure has |
| about them. Unfortunately, they do suffer wear | | | | dissipated. It enters the evaporator where it is |
| and tear. They can break down for a variety of | | | | dehumidified prior to its release. The refrigerant |
| reasons, and fail to perform their respective jobs. | | | | then leaves the evaporator and travels back to |
| The technology used to design your vehicle's | | | | the compressor to start its journey over. |
| heater and A/C has evolved over the last several | | | | Meanwhile, cold air is blown through your car's |
| decades. But problems can still occur. In this | | | | vents with a blower motor. |
| article, you'll discover how the various | | | | Potential Problems That Can Develop |
| components work together to ensure your drive | | | | The most common problems drivers experience |
| is as comfortable as possible. We'll then take a | | | | with their car's heating and air conditioner system |
| look at a few issues you may experience down | | | | include a lack of cold air, intermittent cooling |
| the road. | | | | performance, and noise and odor. Lack of cold air |
| The Job Of The Compressor | | | | is usually due to a lack of refrigerant. This implies |
| Attached to the side of your car's engine is a | | | | there is a leak from the seals or hoses |
| component called the compressor. It is a pump | | | | somewhere in the A/C system. Finding such leaks |
| that is responsible for compressing refrigerant (e.g. | | | | is best left to a trained mechanic who has the |
| R-134a, Freon, etc.) and sending it to another | | | | necessary equipment. |
| component called the condenser (described | | | | Intermittent cooling is often attributable to an |
| below). In order to fulfill this responsibility, the | | | | obstruction caused by moisture. Finding the |
| compressor intakes low-pressure gas from a part | | | | obstruction, similar to locating a refrigerant leak, |
| called the evaporator. The compressor | | | | can be challenging unless you have access to the |
| pressurizes the gas - heating it in the process - | | | | proper diagnostic equipment. The problem may |
| before sending it through the system. | | | | also be triggered by an electrical failure that |
| The Condenser And Expansion Valve | | | | prevents the compressor clutch from engaging. If |
| Your A/C system's condenser appears similar to | | | | the clutch fails to engage, the compressor will not |
| your cooling system's radiator. Moreover, it works | | | | work. |
| in a similar manner. Once the high-temperature, | | | | If you hear your car's A/C system making |
| pressurized gas from the compressor reaches | | | | excess noise, have a mechanic check the |
| the condenser, it undergoes a process through | | | | compressor. There's a high likelihood the |
| which heat is removed from it. During this | | | | component is about to fail, and will need to be |
| process, the refrigerant gas is turned into | | | | replaced. If you smell a musty odor coming from |
| pressurized liquid before it leaves the condenser | | | | the vents, mold has likely grown on the |
| on its way to the expansion valve. | | | | evaporator. This occurs because moisture collects |
| The expansion valve regulates the amount of | | | | on the evaporator's surface (recall that the |
| refrigerant that reaches the evaporator | | | | component dehumidifies the liquid refrigerant). |
| (described below). When you modify the | | | | Don't ignore the odor. Have the mold cleared out. |
| temperature control in your vehicle's cabin, you | | | | The heating and air conditioning system of your |
| are adjusting the setting of this component. The | | | | vehicle should operate without incident for years. |
| higher the temperature setting, the less | | | | When problems occur, however, the repairs are |
| refrigerant that is allowed to pass through to the | | | | best left to a mechanic. |
| evaporator. | | | | |