Auto AC Repair

Auto Air Conditioning Repair & Service in San Antonio, TX

Auto Service Experts Car AC / HVAC Mechanic Specialists


Auto AC System Operation Auto Service Experts


Automotive Air Conditioner Components

Our San Antonio auto AC repair shop has been providing top quality repairs & exceptional service in our local community and nearby areas for over 15 years. We guarantee honest and upfront pricing, and back our work with the best warranty around. Our ASE certified HVAC specialists are experts in diagnostics and can quickly and accurately pinpoint the cause of your car's air conditioning problem. We have the proper equipment, experience, and high-quality parts to restore your air conditioner to like new performance. Same day service is available in most cases. Call to schedule your FREE AC Check, an AC leak inspection, or AC service today, and let us make sure your vehicle is ready for the summer heat!


Our ASE certified HVAC mechanics are also trained & experienced in repairing hybrid car air conditioning systems.


Auto AC Repair Diagnostics

Auto Service Experts auto air conditioner diagnostic includes hooking your vehicle up to the latest AC machine and computer scanners. This specialized machine checks high pressure and low pressure readings, and is used to determine if your car air conditioner is low on Freon. If so, it can recover and add Freon to the correct vehicle manufacturer recommended amount.



Auto ac evaporator case repair in San Antonio TX 78216

 AC Evaporator Case Replacement


FREE Auto AC Checks

In a FREE AC inspection, our mechanics check for visible Freon oil seepage on all lines to the compressor, condenser, and firewall. We inspect all fuses, high & low pressure readings, and the control panel switches. We also check the fan clutch or electric fans and check for debris restriction in the front of the condenser. This condition will cause higher engine temperature and result in poor AC performance. There can be several other causes of high engine temperatures, including radiator leaks or other engine cooling system problems. If your car or truck engine overheats, take it to a mechanic shop near you for diagnosis right away to avoid major engine damage (extreme overheating can cause complete engine failure which requires a complete rebuild or replacement to repair). Finally, we check the level of Freon and ensure that the compressor is engaging. Through this thorough inspection system, our technicians are able to quickly detect if you have an AC leak or other common problems affecting HVAC performance


AC Dye Tests

If the vehicle is too low on Freon and the compressor will not turn on, or if the leak is small and impossible to see with the naked eye, you may require a dye test to determine the source of the leak. A dye test involves injecting fluorescent dye into the car's air conditioning system and running it until traces of the dye (visible under UV light) can be seen at the location of the leak. The fluorescent dye helps to point out hard to detect leaks because freon is transparent and therefore impossible to notice as it escapes the system. Dye tests are performed as a separate service.


Vacuum Test

Refrigerant and air are sucked from the unit with a vacuum pump which creates a vacuum within the system. It is then monitored with a vacuum gauge for a period of time, possibly overnight to detect small leaks. If the system does not hold the vacuum, this indicates the presence of an AC leak. The amount of vacuum loss is recorded to determine whether there is a minor or major leak.


AC Electrical Diagnostics

A certified HVAC mechanic will check to make sure there is power from the electrical system (or a pulse with a signal) to the compressor. We check all fuses and relays. If there is an electronic problem beyond the fuses and relays, it may be a computer control problem due to loss of signal. Computer control signal loss problems are repaired as a separate service.


*** While we are not known for frigid weather here, it is also important to have your car heater repaired at the first sign of problems. If your car heater is not working, it could mean that there are problems within the cooling system which could lead to major engine damage!


2010 Jetta TDI Auto AC Compressor Kit Replacement San Antonio

AC Compressor Kit Replacement on 2010 Volkswagen Jetta TDI

Including Compressor, Condenser, Expansion Valve and Receiver Drier

Auto Service Experts HVAC mechanics do not use rebuilt compressors because the savings of a rebuilt compressor is minor compared to the difference in longevity and performance. In most cases new compressors only cost around $20- $40 more, last much longer, and perform better than rebuilt compressors.


Cabin Air Filter Change or A/C System Cleaning

Your car's air conditioner is not just responsible for keeping you cool, it also filters and conditions the air you breathe while driving or idling in traffic. The AC system can become clogged when debris and contaminants build up over time. If not properly serviced, bacteria, allergens, mildew, and mold grow inside your vehicle air conditioner, which leads to foul smelling air coming from the vents and can even make you and your family sick!


Most modern automobiles come equipped with cabin air filters located either behind the glove box or in the air intake vents in front of the windshield. These filter and clean air as it enters the heating, ventilation, & air conditioning system, known as the HVAC system. They block and trap dust, pollen, pollutants, and other contaminants before it enters the passenger cabin area, therefore, a dirty cabin air filter can result in the air you breathe inside your vehicle being of poorer quality than the outside air. Cabin air filter replacement is usually recommended every 15,000 miles (or every 5th oil change) but may be necessary more often if driving in heavy traffic congestion or a location with a high level of pollution. If your car or truck does not have a cabin air filter, ask about a cleaning service to eliminate bacteria, mold, and unpleasant smells coming from within the system.


When Should You Have Your Car Air Conditioner Serviced?

• Yearly, Before It Gets Hot!
• As Soon As you notice any decline in your auto AC performance, air is not blowing through the vents properly, or air is not cold.
• If you notice a foul odor or musty smelling air coming from the vents.


AC Service Includes:

• Inspect lines and hoses for corrosion and leaks
• Check high and low pressure readings
• Test output air temperature on the coldest possible setting
• Change / clean refrigerant
• Our mechanics are careful to follow environmentally safe refrigerant handling and disposal procedures as outlined in the Environmentally Sustainable Actions Certification Program.

Benefits of Service:

• Stay cool and comfortable regardless of Texas weather!
• Keep the cost of repairs and replacement parts down by keeping up with regular maintenance.
• Protect your lungs from harmful mildew, mold, bacteria, allergens, and pollutants.


We back Our Auto Air Conditioning Repairs and Services with the Best Warranty in the Business!

 AC Compressor kit replacement 2003 Chevy Blazer


Air Conditioning System Operation

Refrigerant / Freon

AC refrigerant is a chemical compound used to absorb and transfer heat in a refrigerant cycle. It is commonly referred to as Freon, which is actually a trademark name. An automotive air conditioner incorporates several components which work together to circulate, compress, cool, and condense refrigerant. Refrigerant is changed from a gas or vapor state into a liquid state, then back into gas in a continuous cycle. R-12 refrigerant was used in most vehicles until it was banned in 1994 and replaced by the more environmentally friendly R-134a refrigerant. Today's automobile manufacturers (including GM) are beginning to use HFO class refrigerants such as R-1234y & R-744 which offer increased energy efficiency, are more cost-effective, and have less of a harmful effect on the ozone layer, therefore contribute less to global warming.


***An AC recharge should only be performed by a professional technician using specialized equipment which recovers & recycles refrigerant, minimizing environmental damage.



The AC compressor is sometimes referred to as the heart of a car's air conditioning system because it is responsible for supplying the system with Freon, or the blood. Freon is a liquid refrigerant which is pumped into the compressor in gas form through the suction port. This gas is then pressurized within the discharge port. The compressed Freon is circulated through a series of different sized cylinders and hoses which create alternating vacuum and pressure, and an expansion valve designed to make the gas contract and expand. Some compressors have a rotary/vane design, and others use pistons and rods to connect to the main shaft. Compressors receive power from a drive belt in the engine. Pressure and cabin temperature inside the compressor are moderated by controls, and refrigeration can be turned on or off by an engagement clutch which is electrically controlled.


Air Conditioner Repair on Nissan Rouge

Nissan Repair at Auto Service Experts - Auto AC Compressor Kit Replacement on Nissan Rouge



From the compressor, the gaseous Freon is pumped into the AC condenser. The condenser uses the engine fan's cold air to reduce the temperature of the gas and turn it back into liquid. This liquid flows through a filter which collects all foreign contaminants, into receiver-driers (Expansion Valve System), or accumulators (Orifice Tube System), where it is stored.


Orifice Tube System / Accumulator

The AC orifice tube system is designed to keep Freon from flooding the evaporator or entering the compressor in liquid form. These systems control the Freon flow from the accumulators to the evaporator. AC accumulators trap moisture within the system, and clean and store refrigerant. The orifice tube changes Freon from high pressure liquid into low pressure liquid and supplies only a mist of Freon to be evaporated back into gas. The orifice tube system is found in most domestic cars, trucks, and SUVs.


Expansion Valve System / Receiver-Drier

Most foreign or import vehicles are equipped with an AC expansion valve system which takes the place of the orifice tube system. The systems use receiver-driers instead of accumulators, which are very similar in operation and function, with the major difference being where they are located within the air conditioning system. A receiver-drier is connected on the high pressure side, and an accumulator is on the low pressure side.



Compressed refrigerant is transferred from the condenser to the AC evaporator. Excess condensation is allowed to escape the evaporator through a drain tube. This condensation can be seen dripping beneath the vehicle and may leave a substantial puddle. This is normal, although it is sometimes mistaken for an AC Leak. From the evaporator, the gaseous freon returns to the suction port of the compressor to repeat the process.


Air Conditioner Components which periodically need Service:

Common Car Air Conditioner Problems often involve repairs or replacements of one or more of the following components:

• Compressor
• Condenser
• Liquid Line
• Orifice Tube
• Receiver/Drier
• Accumulator
• Control Head
• Low Pressure Switch
• Amplifier
• Ambient Temperature Sensor
• Dual Climate Control
• Evaporator
• Cabin Filters
• High-Pressure Switch
• Vintage Air
• Manifold Hoses
• Blend Door Actuators
• Evaporator Cases
• R-12
• 134-A
• Retrofit
• High and Low Fittings
• Blower Motors
• Relay

AC Stop Leak Cans Cause Major Damage

Auto Air Conditioning Compressor Replacement due to damage from AC stop leak


When faced with the need for auto AC repair, it may be tempting to try and fix the problem yourself with a can of stop leak. These are not cheap, quick fixes! They are actually known in the automotive industry as "suicide cans" because most of them cause serious damage to car air conditioning system components. Repairing this damage (which often requires replacing major components or the entire system altogether) is much more costly than simply having a leak repaired by a qualified auto AC mechanic. 

Auto AC Service Benefits

Automotive Air Conditioner Service Recommendations

AC service replaces refrigerant which contains oil that is necessary to lubricate and protect the system, and helps to prevent more costly car air conditioning repairs in the future.

Auto AC Repair Shops Near Me

AC evaporator case replacement Toyota Hybrid car at our shop.


 Many people ask "With all of the local auto AC repair shops, how can I choose the best one and ensure that I am getting the highest level of service, and most value for my money?" There are several ways to quickly research and judge the quality of an auto repair facility in your area before trusting them with your vehicle. Auto Service Experts Blog discusses what to look for and what to ask when searching for a trustworthy and reliable local mechanic shop, as well as many more common automotive repair questions.

Auto Air Conditioner Performance Tips

Tips to increase your car's air conditioning system performance

 Cabin Air Filter for AC Performance


If your auto A/C produces a foul smelling odor, using the outside air mode rather than the recycled air mode will help to reduce odor and provide more fresh air. Your vehicle may be in need of a cabin air filter change, or A/C system cleaning service.


Even if your A/C is blowing cold air, a clogged cabin air filter blocks the majority of that air from reaching you. Restricted cabin air filters cause the system to work much harder while providing little relief from the heat!


Car air conditioning systems require a large amount of horsepower to operate (usually 15% - 20%) therefore reduce fuel economy quite a bit. 


Operating your car's A/C system generates a lot of heat in the engine and strain on the vehicle's cooling system. A well maintained cooling system will not only be better able to handle this extra work load, but will also prevent the engine from overheating which can result in costly repairs.


If your car is in a secure location, leave the windows cracked while parked. This will keep the interior temperature from rising as high, allowing your A/C cool down the cabin more quickly.


When you start your car, turn the A/C on the coldest setting uising maximum blowing speed and roll all windows down completely. This will force hot air out of the vehicle and generate circulation which willl speed up the cooling process.


Turning on the air recirculation mode once the cabin air temperature is sufficiently cool allows the air conditioning system to operate more efficiently.


With automatic temperature control AC systems, the cabin air will reach your desired temperature faster if you first set it at the coldest setting, then readjust to desired temperature as needed. 


Once the car is sufficiently cooled, use lower blower speeds which allow the A/C system to generate colder air.

ASE master technician Carlos Rodriguez

(210) 495-6688
Auto Service Experts

13050 San Pedro Ave. San Antonio, TX 78216

Mon-Fri 8:00am - 6:00pm