5 Reasons Your Car’s A/C Isn’t Working — and What to Do About it

Is the car's AC working?

Summer is fast approaching, and with spring temps predicted to be above average in 2024, you may be cranking that A/C earlier and more often than before. 

What happens when you hit that A/C button and you’re met with warm air instead of a blast of cool relief? In this blog, we’ll explore common reasons your A/C may not be working and recommend getting it back up and running. 

Understanding Your Car’s A/C System

You know your air conditioner is essential for summertime driving comfort, but how exactly does this crucial component work? It might not be exactly what you think. 

Your A/C isn’t actually producing cold air. Instead, it absorbs the hot air from your car’s interior, cools it down and redistributes the cooled air back to the cabin. 

Your A/C consists of four primary components: the compressor, the evaporator, the condenser and the thermal expansion valve. These work together to expel hot air and humidity and send cooled air back through your vents. 

  1. Compressor. As it passes through the compressor, refrigerant is compressed and converted into a high-pressure, high-temperature gas. 
  2. Condenser. The hot, gaseous refrigerant travels to the condenser, where air pulled from the front of the vehicle cools the gas to produce liquid condensation. 
  3. Thermal expansion valve. Liquid flows into the thermal expansion valve, which meters the amount of liquid and converts the high-pressure liquid refrigerant into a low-pressure vapor that enters the evaporator core. 
  4. Evaporator. Inside the evaporator, the refrigerant absorbs heat from the vehicle’s interior, causing the core to cool. The blower motor circulates air over the cooled evaporator core, distributing cooled air throughout the vehicle’s cabin. 

5 Reasons Your Car’s A/C May Not Be Working

If any of the above components are damaged, your A/C may function poorly or stop working altogether. Here are the top five reasons your A/C may not be working. 

1. Leaks. Most air conditioner problems are caused by a leak somewhere in the system. Refrigerant travels throughout the A/C system, so leaks can happen anywhere. They are most common at connection points and can happen when rubber seals and hoses break down over time. 

Not only does this leave you without that much-needed blast of cold air, but cracks can let moisture into the A/C system and possibly cause corrosion. 

2. Compressor Issues. If the compressor malfunctions, the refrigerant can’t move through the system. One of the primary causes of compressor failure is sitting idle for long periods of time. You may also find an issue with the compressor clutch being stuck either in the on or off position. 

3. Condenser Problems. The condenser cools the air. If this component fails, you may experience less cool or even warm air coming out of your vents. The culprit could be leaking or clogs in the condenser. 

4. Broken Cooling Fans. The cooling fans are responsible for pushing cold air through the vents into your vehicle. When they malfunction, you won’t feel that cool air at all. There are a few reasons your cooling fans may break, including blown fuses, electrical shorts or cracks. 

5. Electrical Issues. The A/C system in your car runs on electricity. Damaged wires, blown fuses or broken sensors can cause the interconnected system to come to a grinding halt. 

These issues are often pretty straightforward for a qualified technician, but you shouldn’t delay fixing them. Malfunctioning electronics in your A/C system can lead to acid buildup, which may cause serious damage to your vehicle. Letting these issues ride may result in needing to replace the entire air conditioning system. 

Diagnosing and Fixing the Problem

You probably don’t give your air conditioner much thought until it starts blowing out warm air or not blowing at all. This is usually the symptom that sends people into the repair shop. But there are other signs your A/C is on the way out. 

  • You smell something. If your A/C smells musty, you may have a dirty filter. Dust, water and even mold can collect on the A/C filter or in vents, putting out an unpleasant odor and, in some cases, activating allergies. Bring your car in right away if you smell anything off. 
  • You hear something. If you hear unusual sounds like clanging, grinding, squeaking or rubbing when your A/C is running, there’s likely something amiss. Anything from a failing compressor to a bad blower motor can cause odd noises. Have your mechanic take a listen to help pinpoint the cause. 
  • You feel something. More specifically, you feel something wet. If there’s water pooling inside your car while you’re running the A/C, it might mean a blockage. 
  • You feel (almost) nothing. Maybe the air is circulating, but it’s weak and doesn’t seem to be up to the task of cooling your car’s interior. This may signal a problem with the vent control, blower motor or air filter. 

How Much Does A/C Repair Cost? 

The cost of A/C repair or replacement depends on the issue and extent of the damage. On average, according to a Consumer Affairs survey, an A/C recharge where a technician fixes a leak and then replaces lost refrigerant typically ranges from $430 to $521, while a compressor replacement may set you back up to $2,500. 

Be sure to add an A/C check to your regular maintenance schedule to catch problems before they become major (and expensive) issues. Take advantage of moderate spring weather and make an appointment to get your A/C evaluated today before the heat of the Ohio summer kicks in. Your trusted neighborhood technician can take a look, diagnose any problems and get you back on the road — and fully cooled — in no time. 

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