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What is a car AC recharge kit?

Air conditioning vents supplying a cool flow of air to the cabin.

On a hot day, you get behind the wheel, start your car and immediately activate the air conditioning system. As expected, the initial airflow is very warm, but that should change in mere moments as the system kicks in to deliver cool air. But what if the air never cools? If your climate control is set correctly and this still occurs, it’s likely time for some maintenance. A car AC recharge kit may be just what you need to solve this problem and bring relief to everyone in your car’s cabin.

How Car AC Works

Recharging a car's air conditioning system.A vehicle’s air conditioning system consists of a compressor, a condenser, an expansion valve or orifice tube, a receiver/drier or accumulator, and an evaporator. The compressor converts the refrigerant into a fluid, which then flows through a line to the condenser. The condenser removes the heat from the refrigerant and then pushes it through to the expansion valve or orifice tube.

From the tube, the fluid passes through the receiver, removing moisture from the refrigerant as it moves to the evaporator. The evaporator pulls heat from the air as it passes through the core, and the cooled air is directed into the cabin. As the refrigerant inside the lines boils, it absorbs heat from the air and heads back to the compressor as a hot gas, and the process repeats.

What Is a Car AC Recharge Kit?

Assuming that the various parts of your AC are working, a system tune-up is in order, and shopping for a car AC recharge kit is the best move. Simply find the refrigerant type that matches the one mentioned in your vehicle’s owner’s manual, and purchase it. A sticker on the front frame of the engine compartment or the inside of the hood may also include this information.

A typical AC recharge kit includes a canister with an attached hose, a coupler and a pressure gauge that will help you avoid underfilling or overfilling the system. Pro tip: If you’ve already recharged the air conditioner within the past year, then you may have a small leak. Instead of wasting refrigerant that may leak right back out, look for a recharge kit that includes a sealant to eliminate small leaks.

Regardless of whether or not you have a leak, you may still have to recharge every so often. The kit you’ll need to do this can be purchased at most NAPA AUTO PARTS stores for under $100.

How to Recharge the AC

After you check your manual to locate the AC system in your engine bay and pop the hood, follow these steps to recharge your AC:

  1. Check the outside temperature with a temperature gauge or thermometer.
  2. Adjust the recharge kit gauge to match the outside temperature. An arrow on the gauge allows you to target the right temperature and match the correct PSI. For example, if the outside temperature is 80-degrees Fahrenheit, the gauge would read 45 PSI.
  3. Start the car, and then attach the temperature gauge to an air conditioning vent. Next, set the AC to its coldest setting.
  4. Put on eye protection and gloves.
  5. Attach the hose to the kit, and shake the can. Screw the adapter on the end of the canister’s hose into the air conditioner’s low-pressure service port. Typically, the cap is marked with an “L” to identify it. Also, the adapter will only connect to the low-pressure port, so there’s no chance of an accidental connection.
  6. Per your kit’s instructions, squeeze the trigger, tilt the bottle back and forth, and check the readout after 10 seconds to avoid overcharging. Resume the process until the correct amount of pressure is reached.
  7. Disconnect the kit and reconnect the low-pressure cap.

Recharged AC

The final step is to check the temperature of the air flowing through the vents. It should read substantially lower than before as a consistent flow of cool processed air is delivered to the cabin.

Check out all the air conditioning service and repair kits available on NAPA Online, or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on air conditioning repair, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

Photo courtesy of Pexels.

Matthew C. Keegan View All

Matt Keegan has maintained his love for cars ever since his father taught him kicking tires can be one way to uncover a problem with a vehicle’s suspension system. He since moved on to learn a few things about coefficient of drag, G-forces, toe-heel shifting, and how to work the crazy infotainment system in some random weekly driver. Matt is a member of the Washington Automotive Press Association and is a contributor to various print and online media sources.

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