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Auto AC Repair

A lot of times, people won't service their car's AC system until after it fails or isn't working as great. 12th Street Auto suggests that a vehicle's air conditioning should be serviced or checked, typically, every two years. But sooner is better than later. A damaged AC system can be expensive to fix or replace. But if a problem is detected early on, a car owner can save a lot of money. Call the professional automotive technicians at 12th Street Auto Care Center to schedule your vehicle's air conditioning repair today.

ASE and AAA Approved Auto AC Repair Shop

Our automotive repair shop has some of the finest and most trustworthy ASE and AAA Approved mechanics to repair and service your vehicle’s AC System. By getting your car’s air conditioning serviced or checked at 12th Street Auto, you are guaranteed satisfaction, and you’ll be saving money. We will examine and repair any vehicle make and model with any air conditioning system.

AC System Components

There are a lot of parts that go into keeping your car’s cabin cool. With safety being 12th Street Auto’s main concern, we also care about your comfortability in your own car. Overheating can be a serious health risk on an extremely hot day. But we’re here to do the job well and keep you out of harm’s way. Along with offering the assurance of accurate diagnoses with vehicle troubles, we also offer affordable prices and financing, so you don’t have to worry about a thing.


A vehicle’s air conditioning system begins with the AC compressor. It is the unit in the cycle that makes the refrigerant hot and highly pressurized, and then pumps it into the condenser. On most vehicles, AC compressors operate with an engine-accessory belt. If a compressor is working correctly, your AC should be at peak performance. If the AC, however, is failing to blow out cold air, the belt could have slipped or be worn, or refrigerant could be leaking.

Signs of a failing compressor include: higher cabin temperatures than what is normal, loud noises when the AC is running, and an unmoving compressor clutch.


Once the pressurized and gaseous refrigerant leaves the compressor, it winds through the radiator-like condenser and becomes a liquid. Air from the exterior of the car passes through the condenser and helps the refrigerant to lose its heat and become cool. Then, the cooled liquid refrigerant leaves the condenser and enters the drier, which is also called the receiver. If cool air isn’t blowing into the cabin of your car, it could be that the air conditioning condenser is clogged or the cooling fan is disabled.

Signs of a failing condenser include: your car overheating while being idle, a burning smell while the AC is on, and lukewarm air blowing out of your dashboard.


Before the refrigerant becomes cool again, it gets filered through the receiver, also called the drier. Here, the receiver traps any water moisture that may have been circulating inside the AC System with the refrigerant. It also retains unwated particles and impurities. Unwanted moisture and foreign particles can case corrosion within your car’s air conditioning. We recommend that your vehicle’s receiver be replaced every 3 years, or when your vehicle’s compressor or condenser are replaced as well. If your receiver is failing, it could be that the receiver broke on the inside, which could make noise or leave an unpleasant smell in your car.

Signs of a failing receiver/drier include: a moldy or mildewy smell when you turn on your AC, a rattling noise while operating, and visible refrigerant leaks.

Thermal Expansion Valve (TXV)

High-pressure and low-pressure plays a significant role in the air conditioning of your car. When the refrigerant leaves the receiver, it is still high-pressured. But when it enters, then leaves, the thermal expansion valve (TXV) it becomes low-pressured, and cooler in temperature. The TXV also controls how much refrigerant passes through to the evaporator, which will then help to blow out cool air from your dashboard. If your thermal expansion valve is failing, it can cause performance issues, blowing out colder air than usual, or warm air when set to cold.

Signs of a failing TXV include: your AC compressor is always running, performing worse than normal and is blowing out warm air, and the formation of frost on AC evaporator or your dashboard vents.

Sensing Bulb

The sensing bulb is attached to the thermal expansion valve, which helps to regulate the amount of cooled refrigerant that passes through to the evaporator. The bulb is filled with refrigerant that is separate from the cycling refrigerant, and is set against the outlet of the evaporator. Having it there signals to the TXV, through pressure, how much cooled refrigerant to release into the evaporator. If your sensing bulb proves defective, it cannot regulate the flow of cooled refrigerant, thus allowing you and the TXV no control over how much refrigerant passes through.

Signs of a defective sensing bulb include: higher or lower than usual refrigerant super heat value at the evaporator’s outlet, a starved evaporator.


Out of the evaporator comes the cool air that is blown out of your vehicle’s dashboard vents. What really happens is that the evaporator removes the heat from your car by blowing warm air across the evaporator finned coils and tubes. Then, the cooled refrigerant absorbs the warm air in the tubes, turns into a cold vapor, and blows out cool air. Then the cycle starts all over again with the cold vapor in the tubes returning to the compressor to be heated and pressurized. If the performance of your AC system is not what it normally is, it could be that your evaporator is failing or damaged.

Signs of a failing evaporator include: the AC compressor not activating, the AC’s temperature varying no matter the setting, a sweet smell in your vehicle’s cabin, and weak cool air being blown out.

Napa Service Assistant

You don’t have to be an expert to know that preventive maintenance is the best way to make sure your vehicle is running properly. Use our interactive vehicle tool to learn about the maintenance and services your NAPA AutoCare Center can provide.

Napa Interactive Maintenance Tool