Frequently Asked Questions:
Your vehicle’s air conditioning system is designed to have a specific and exact amount of Freon in it. An A/C recharge completely evacuates all Freon, air, and accumulated moisture from the system, and then reinserts the Freon at the vehicle manufacturer’s specifications.
When do I need an A/C recharge?
Whenever a compressor, hose, or other component is replaced that involves opening the air conditioning system, an A/C recharge should be done afterward to ensure the system’s Freon is at the correct level.
My air conditioning isn’t getting cold. Will an A/C recharge or a Freon boost fix it?
It depends what the root problem is. If the root problem is related to a bad compressor, fan, belt, or other mechanical component of the system, an A/C recharge or Freon boost will not help. However, if the root problem is low Freon due to a leak in the system, an A/C recharge or Freon boost will likely fix the issue, but only temporarily (much like putting air in a leaking tire).
What are the most common problems experienced with a vehicle air conditioning system?
The most common complaints we hear with car A/C systems are...
- A/C not blowing cold air
- A/C takes too long to get cold
- Vehicle shakes when the A/C is on
- No air coming out of the vents
- Fog coming out of the vents
- A/C smells funny
Why is my car air conditioner not blowing cold air?
The most common causes are...
- Low Freon due to a leak in the system
- An electrical issue
- A mechanical issue with a system component (compressor, fan, belt, etc)
When a vehicle is brought in that won’t blow cold air, the first thing done is to hook the vehicle up to a set of special gauges to check the pressure of the A/C system. These gauges can help identify low Freon levels (which indicates a leak in the system), or a non-functioning mechanical component in the system. A non-functioning component can be due to an electrical issue keeping the component from receiving power, or it can be due to a failure of the component itself.
How do you diagnose an electrical or mechanical component failure?
Determining if a major component of the car A/C system isn’t running is usually pretty straightforward. For instance, a technician only has to look at the fan or A/C belt to determine if they are running or not and pressure gauges can determine whether or not the compressor is running.
Once we’ve determined that a specific component is not running, the next step is to determine whether it’s an electrical issue keeping the component from drawing power, or whether it’s a mechanical failure of the component itself. This is usually done by testing the component with a volt meter. If the component is not drawing power, it indicates an electrical issue and electrical diagnostics will be necessary. If the component is drawing power but still not running, it indicates a problem with the component itself and the component will usually need to be replaced.
How do you locate a Freon leak?
If we determine that the Freon level of the system is low, this indicates a leak somewhere in the system and the next step is to determine where.
Major leaks are generally fairly easy to spot and are usually due to broken components in the system. Smaller, slower leaks are much harder to spot. These require a dye test. With a dye test, fluorescent dye is injected into the A/C system, and the customer is instructed to drive the car like normal for a few days to let the dye work through the A/C system. A special leak detection lamp is then used to try to spot where the dye is leaking from and uncover the location of the leak. Not all portions of the A/C system are visible while the vehicle is fully assembled though, so this is a process of elimination. The visible portions are checked first. If the leak is not found there, partial disassembly of the vehicle may become necessary to check the portions that are not visible. Once the leak is found it is usually a matter of replacing the leaking part, and then evacuating and recharging the system.
Can I add a little Freon to make my car’s A/C colder?
Yes, but keep in mind that the vehicle’s A/C system is designed to have a very specific amount of Freon in it, so care and caution must be used. If attempting to add Freon, the Freon should be added slowly with the bottle in an upright position, with the A/C system on and running, regularly checking if the air has gotten cold. As soon as the air is cold, stop adding Freon.
What happens if I put too much Freon in my car’s A/C?
Too much Freon will cause the A/C system pressure to be too high, which can cause extensive damage to the compressor and other system components, and lead to expensive repairs.
Why does my vehicle’s air conditioning take so long to get cold?
This is most likely caused by either low Freon due to a leak, or a faulty component in the system. A similar series of diagnostic steps will be taken as when the vehicle is not blowing cold air at all. See above.
Why does my vehicle shake when the A/C is on?
The A/C compressor draws a lot of power and therefore puts a lot of strain on the engine when activated, but not usually enough to cause a noticeable vibration. However, if the engine is already experiencing another issue that is causing it to vibrate, the additional strain of the compressor will noticeably exacerbate it. Usually the correct course of action is diagnostics to determine the root cause of the engine vibration.
Why isn’t there any air coming out of my car’s vents?
If your car’s ventilation system is working sub-par, or not at all, it could be because a fuse has blown. With a blown fuse, the electrical power gets cut off completely and the system is unable to operate.
Other reasons could relate to a malfunctioning or damaged blower motor, a broken hose, or a clogged air intake system. Diagnostics will be necessary to determine the specific cause and correct course of action.
Why is there fog coming out of my A/C vents?
If it’s hot and humid out it could just be as simple as the cold, dry air from the A/C coming into contact with the warm, humid air in the cabin. If the fog persists even after the cabin is sufficiently cooled, it could be a clog in the air intake drain. The air intake is where outside air enters the system before being cooled, and is located at the bottom of the windshield below the wipers. The air intake is built with a drain to get rid of water that gets in during rain. If this drain gets clogged (broken down leaves are the most common culprit), water will remain in the air intake chamber which can lead to water vapor in the A/C system. Removing the clog will usually fix the issue.
Why does my vehicle A/C smell funny?
If there is a weird or distinct smell venting from your A/C system, it could be due to mold or bacteria buildup and need cleaning.
If the smell is sweet or fruity, you should have your system inspected – there may be an antifreeze leak in the cooling system. Even though the smell is sweet, antifreeze chemicals can be harmful to your health.
How do I know when my A/C compressor is bad?
When diagnosing a vehicle air conditioning issue, the vehicle is hooked up to special gauges to determine the pressure in the A/C system. The readings on these gauges can reveal to a technician when a compressor is not working. From there, it must be determined whether it is an electrical issue keeping the compressor from drawing power, or a problem with the compressor itself.
Can I drive my car with a bad compressor?
A bad compressor will not hamper the car’s ability to run. The compressor is the heart of the vehicle’s A/C system though, so it will mean that there will be no air conditioning in the car, and it will also reduce the effectiveness of the vehicle’s defrost / dehumidifying system which makes use of the A/C system (even in winter) to ensure the air being blown out is dry. A poorly functioning defrost system could create a potential safety issue.
Why do I need to replace my receiver drier?
The compressor and the receiver drier are interrelated, so if you need a new compressor, the recommendation for a receiver drier replacement is normal. Most compressor manufacturers will not warranty the compressor unless the receiver drier is also replaced.
If the compressor is fine but the receiver drier is leaking, clogged, or if there is too much moisture, the receiver drier needs to be replaced.