AC not working inspection
The in’s and out’s of Your Car’s AC System: Why It Stopped Working and How to Fix It
The air conditioning (AC) units on many folks’ cars are the pride and joy of the vehicle. Being able to perfectly control the interior climate of the car, regardless of what is occurring outside, is pretty much a modern marvel. Without the AC, driving throughout the hot parts of the year is an absolute struggle. That’s why, when the AC stops working, it puts a knot in our stomach and a panic in our bones like a good horror movie.
Keep on reading to learn about the complexities of the automobile air condition systems, and what to expect if yours stops working.
The Air Conditioning System
The air conditioning system in your car is more or less comprised of 8 really important components:
The compressor is the heart and soul of the AC unit. It is powered by the serpentine belt and pressurizes the refrigerant. The refrigerant is what keeps on the air coming from the AC cool. Most cars use a refrigerant called R22, also known as Freon.
The clutch on the compressor controls the compressor cycles. It is an electromagnetic component that engages and disengages the compressor to release the refrigerant. The clutch, then, makes sure that the refrigerant is properly pressurized and ready for usage.
The condenser takes the hot refrigerant and cools it down. It also reduces the pressure. Essentially, this transforms the refrigerant into a liquid so that it can be used in the AC system.
The receiver or dryer is only equipped in vehicles with a thermal expansion valve. The receiver, also known as the dryer, protects the AC unit from damages caused by unwanted liquids and particles. It separates gas from liquid, movies mixture, and discards contaminants.
The accumulator is only equipped in vehicles with an orifice tube. The accumulator has roughly the same function as the receiver. It eliminates mixture and debris, while also controlling the amount of refrigerant that goes into the evaporator. The accumulator also stores excess refrigerant.
Thermal Expansion Valve or Orifice Tube
Depending on your car, the AC system will either have a thermal expansion valve, or an orifice tube, but not both. Either way, they both accomplish the same thing. Both are located between the condenser and evaporator and are in charge of regulating the amount of refrigerant that enters the evaporator.
The evaporator is what does the actual cooling in your car. The evaporator removes humidity from the cabin and cools the air that passes over it. It is controlled by a clutch switch that prevents it from freezing.
The blower motor is responsible for blowing the cool air that has passed over the evaporator through the vents in your car. The fan speed is controlled by a central control head, and the doors of the vents control the direction of the blowers.
How to Fix the AC
The AC system in your car can be susceptible to failing parts, and underperformance. When this occurs, there are a few common reasons why:
- Blown fuse: oftentimes the simplest solution is replacing a fuse. Electrical tests will be performed to test the voltage of the AC fuses.
- Damaged receiver/ dryer: if the air is not blowing cold, and you have moisture build-up in the cabin of your car, this means the dryer is not properly functioning.
- Faulty blower motor: noisy AC systems, and blowers that always operate at full speed reveal an issue with the blower itself, or the resistor
- Dysfunctional condenser: road debris can damage the condenser fins and cooling tubes, which will restrict the flow of refrigerant
- Blown compressor: strange noise or a sudden failure may be a sign of a blown compressor. Other signs of a faulty compressor could be oil or refrigerant leaks.
The strategy for fixing the AC, then, will be determined by what component in the system is actually broken. To diagnose the problem, a mechanic will complete an AC inspection. They will:
- Check the refrigerant
- Use a sniffer to check for leaks
- Test the heater controls
- Check all other system components
Once the inspection is complete, the mechanic will have a better idea of the scope of the issue, and the plan for fixing the problem. They will be able to provide you with a quote for the necessary parts and labor for the repair job.
How Much Does it Cost to Repair my Car’s AC?
The cost for repairs related to your AC system will vary. Some AC fixes are easier than others, and therefore, less expensive. However, other, more complex issues can result in more expensive repairs.
Below is a list of some common AC repairs, and their average prices:
- AC recharge: $100 to $140
- AC hose repair and replacement: $500
- AC compressor clutch repair: $250- $750
- Other Major AC repairs: $1,000 to $4,000
The bottom line is that in most cases, both the parts required and the labor involved is more expensive than repairs related to other parts on your car. AC repairs are often very complex, and therefore require a large labor investment on behalf of trained professionals.
The issues related to AC failures or underperformance can be summed up into four categories:
- Hydraulic problems: lack or excess of refrigerant and lack of compression
- Electrical problems under the hood: Failures of the AC clutch, relay cut-off switches, or controls devices
- Electrical problems in the dashboard: issues with the control head or command motor
- Mechanical problems: failure of components such as the blower motor, evaporator, or AC doors.
If you think your car is having problems with any of the issues talked about above, go ahead and schedule your car for service.