Master Mechanic: Common Issues with Air Conditioning in Cars

Spring is quickly approaching, and summer won’t be far behind it. With changing seasons, comes changes to our driving habits. If you’re like the team at Master Mechanic, you prefer to be comfortable when driving. During a hot spring or summer day, that usually means cranking up the air conditioning. If you’ve started up your A/C, only to find out that it isn’t working properly, you probably want to get it looked after sooner than later.

We asked a Master Mechanic to explain the most common issues with air conditioning systems in cars, and what to do about them.

Why does my A/C have weak airflow?

So you hop in your car, turn on the air conditioning, and expect a cool blast of air. Except, there isn’t one. Now what? At Master Mechanic we hear this problem all too often. Whatever the underlying cause may be, it’s important to get this looked at as soon as you notice it. Putting off a repair to your A/C can cause other parts of the system to fail.

First, use your vent selector to change the air flow to different vents. While you’re turning the knob, take notice of the air flow. If air comes out some vents and not others, your blend door may be stuck.

Blend doors are located inside your A/C unit, and they control which vent air flows through. If blend doors get stuck or damaged, they can block air from flowing properly.

If you’ve ruled out a problem with your blend doors, next, you’ll want to check your car’s blower motor. To test this, start by turning on the A/C. Once again, pay attention to the rate of airflow. Now, switch from A/C to heat. If the air flow is  weak on both settings, you may have a clogged cabin filter or the blower motor may be failing.

My A/C doesn’t seem as cold.

So your air conditioning doesn’t feel as cold as it once did? This is another common problem we see at Master Mechanic. Your air conditioning system is complex and has many different components. It’s best to take your car to your local Master Mechanic who knows exactly what to test for and has the proper equipment to do so.

That said, there’s no harm in checking things out yourself to diagnose the problem.

Inspect your condenser. It’s  located in front of your radiator and should be clear of debris. If it’s really dirty, it can’t function or cool effectively.

Towards the front of the engine, by the grill, you’ll usually find the car’s A/C compressor. It looks like a small motor with a wheel on the end. with the A/C turned on this wheel should be spinning. If this wheel is not spinning, your compressor clutch isn’t working or you may have an electrical issue.

If your refrigerant levels are running low, the A/C system won’t provide any cool air. It’s important to note that refrigerant is not consumed during normal operation, however, if the system is low on refrigerant it is due to a leak. A/C systems can’t just be “topped up” the leak must be located and repaired before more refrigerant is added. Checking levels and for leaks requires specialized equipment so checking for leaks on your own is quite difficult.

One method of checking for refrigerant leaks involves injecting ultraviolet dye into your A/C system, running the car, and checking for leaks with a UV light. If you suspect your refrigerant levels might be low, we recommend calling your local Master Mechanic immediately, before the problem gets worse. When moisture and refrigerant mix together, they form a corrosive acid that will destroy seals and components, causing more issues.

What is that…smell?

Your air conditioner is designed to blow cool, filtered air into your car’s cabin. Unfortunately, many drivers are greeted by a musty odor in their car when they first run the system for the season. In addition to being annoying, it can be harmful to your health. Potential causes of odors in your vents include dirty or old air cabin filters, or mold accumulating on the evaporator case because the drain is blocked.

What do I do next?

Once again, we can’t stress enough the importance of addressing issues with your car’s air conditioning as soon as possible. It could mean the difference between a small fix and a major repair.

Questions or concerns about your car’s air conditioner? At Master Mechanic, we’ll always explain exactly what we find under the hood, and what is required to fix it. When it comes to car repairs, we’re here to help you keep your cool. Contact us today to schedule an appointment!