(408) 340-7755

Air Conditioner Blowing Hot? We Can Fix That

Our qualified mechanics use special equipment to evacuate the old refrigerant, vacuum test the system for leaks and recharge the system using the amount and type of refrigerant specified by the vehicle manufacturer.

Air Conditioning and Climate Control Repair and Maintenance


Summer is the season of overheating--for vehicles, and those inside them.

Here’s how to keep a humming engine and breezy interior.

Most vehicles overheat due to poor maintenance. Coolant, like oil, has a service limit. Over time the coolant evaporates and overheating begins. Fans and coolant maintain an engine’s temperature--a busted fan or insufficient coolant disables an engine.

And that’s just outside--the cabin itself isn’t exactly welcoming. This isn’t a problem if your climate control works.

But that’s not always the case.

Air conditioners can fail in a variety of ways for a number of reasons.

Never assume warm air from the vents automatically means the system’s low on refrigerant.

Below, Quality Tune Up Car Care Center suggests services and precautions worth considering at the beginning of summer:

  • Don’t put tap water in the radiator. Tap water invites foreign minerals that can plug passages and increase wear and tear.
  • If your car overheats, turn off the engine and open the hood.
  • Never twist the radiator cap while it is hot. Not only is the cap itself blistering hot, it’s holding back a rolling boil of chemicals under high pressure. Opening the cap of a hot radiator may cause severe injury from scalding liquid. Wait for the radiator to cool before opening.
  • Continuing to drive an overheating engine can cause severe damage. Consider a tow.

General maintenance

That trusty climate control system works wonders keeping you and your passengers comfortable on those blistering summer afternoon drives.

But when it breaks, conditions quickly deteriorate as hot, stale air pours through the vents.

Have a trusted service advisor check the fluid pressure, duct temperature and cooling fan operation while also inspecting for leaks. A blown fuse or issues with the compressor could also be the culprit.

Of course, auto parts stores sell cans of air conditioning refrigerant, but Quality Tune Up Car Care Center advises against the do-it-yourself route when dealing with such a complex system.

You may end up missing the source of the problem and create more expensive repairs down the line.

If refrigerant has leaked, there’s a good possibility air and moisture have entered the system. Moisture can corrode pipes, creating extensive damage and rotting the system from the inside out.

Below, Quality Tune Up Car Care Center offers insight into what may cause problems with your climate control system:

  • Clogs in the lines may impede airflow.
  • Check all fan settings. Do you notice any cool air when the adjusting temperature?
  • Damaged hoses or a blown fuse. This is a simple and inexpensive fix.
  • Ask your service advisor to inspect the vehicle’s air conditioning compressor. Components of the climate control system may need to be replaced.

Hot air from the air conditioner does NOT always mean “add refrigerant.” It could be a blown fuse--or something entirely different. Point is, trusting a trained expert to diagnose and address the issue remains a far better investment than buying a can of refrigerant at the store and hoping for the best.

Winter Air Conditioning & Climate Control Performance

With separate thermostats for the driver and passenger sides, extra vents for passengers in the backseat and heated seats, modern technology makes it easy to stay comfy and cozy all winter long.

How it works: The climate control system transfers the engine’s heat to the vehicle’s interior. This engine heat is absorbed by coolant—a blend of water and antifreeze—which is carried by heater hoses to the radiator. Then the water pump forces coolant through the engine and heating system. From there it travels to a heater core located in the dashboard and a fan swirls warm air into the cabin.

Keeping such a complex system functioning takes a trained specialist who is trained to deal with modern day climate control systems. Like any other system, climate control is subject to wear and tear. Belts and hoses are made of rubber. Over time, they crack. They can even dry-rot like tires do.

Everything starts with visual inspection. Service techs look for leaks and check the condition of the belts and hoses.

The heating and cooling systems routinely feed off one another, so problems with one may affect the other. Low coolant levels reduce the heater’s ability to warm the interior. Leaks in the heater core, hoses, radiator or cooling system will lead to a lack of coolant and create problems in the system.

Check with your owner’s manual for suggested service intervals to care for the heating system’s components.

  • Know the warning signs. Stains on the passenger side of the dashboard could be the sign of a coolant leak. (Antifreeze runs through the heater core, which usually sits behind or under your dashboard, often on the passenger side.)
  • Check your cabin air filter. The filter captures hair, dust and particulates in the air before it reaches your nostrils. Check your owner’s manual or ask your service advisor how often your cabin air filter should be changed.
  • Hidden problems could be the culprit. A vacuum leak, core failure or stuck thermostat can also cause problems with the heater.
  • Check for the condition for the coolant itself. A 50/50 mix of antifreeze and water is ideal.
  • Simple solutions often exist. Look for clogs in vents that may impede airflow.

Cabin filters & Your Air Conditioning System

Cabin filters became widely used in the late 1990s as a way to reduce allergens.

Today, more than half of all new vehicles utilize cabin air filters for their air conditioning and climate control systems.

Cabin air filters keep the interior of your vehicle clean by removing dust, dirt and pollen. Since it is installed inside the vehicle air conditioning ducts, the cabin air filter operates whenever you use your vehicle’s heater, air conditioner or vent.

Quality Tune Up Car Care Center recommends replacing the filter every 15,000 to 25,000 miles (check your owners manual for manufacturer’s suggestions. Typically, that means changing the cabin air filter once a year for most drivers.

There are exceptions, however. Do you drive in the mountains? Along dusty roads? Are you prone to allergies? Smokey, dust or pollen-filed air quickly can cause your cabin air filter to get clogged quickly.

That could mean changing out the cabin air filter two times or more per year, depending on your driving conditions.

Replacing dirty cabin air filters is not just a comfort issue. Just as a clogged furnace filter in your home reduces the furnace's efficiency, a clogged cabin air filter reduces the efficiency of the heating and cooling system for the car interior.

A clogged filter can also cause a drop in gas mileage as the climate control system works harder to pull air through vents. Additional strain shortens life of the air conditioning motor.

Also, dirty filters increase window haze since particles are not being trapped in the waffle structure. Haze increases glare and dramatically reduces visibility, especially in early fall and winter when the sun is low in the sky.

Cabin air filter replacement vary in price, size and location. Quality Car Care Centers stock a wide variety of cabin air filters on site and usually includes installation at no additional cost for most vehicles.

Installation typically takes about ten to 15 minutes. For some vehicles, installation requires remove removal of glove box, dash console and other components--a process that may take up to an hour.

Once the cabin air filter is installed, you now can breathe easy.

Your air conditioner and climate control system will operate efficiently. And your family will benefit from driving in a clean, allergy free environment.

Read more about our air conditioning service.

Quality Tune-Up Car Care is committed to ensuring effective communication and digital accessibility to all users. We are continually improving the user experience for everyone, and apply the relevant accessibility standards to achieve these goals. We welcome your feedback. Please call Fremont (510) 790-0675, Milpitas (408) 262-3211, San Jose Bascom (408) 377-4764, San Jose McKee (408) 923-5430, San Jose Blossom Hill (408) 629-1371, San Jose Winchester (408) 557-8157 if you have any issues in accessing any area of our website.