Testing the A/C Pro DIY air conditioner repair kit (pictures)

The A/C Pro is a DIY air conditioner recharge kit that retails for about $45 to $50 for the canister and recharge hardware. The hardware includes a recharge hose with low side port connector, pressure gauge, and refill trigger.

The owner of our test vehicle, a 1999 Toyota Corolla, reported that the air conditioning system was blowing warm air. She said, "It doesn't work at all. I'm not sure a recharge will help it."

Before recharging the system, I measured the temperature of the air blowing out of the center vent with the A/C system going full bore for 5 minutes. The thermometer read about 84 degrees Fahrenheit.

The first step is to locate the air conditioner's low side port. This port's location will vary from model to model, but A/C Pro maintains a catalog of port locations on its Web site. The A/C Pro's connector will only fit on this port, so there's no chance of accidentally connecting to the wrong side of the system.

Before recharging, there are a few more things to check. First, make sure that the car is running and that the A/C system is running. Now, check that the compressor is actually spinning. If not, you may have bigger problems than this system can fix. Finally, attach the A/C Pro's connector and measure the current pressure of the system. If it's low, begin the charge.

After removing a safety collar from the A/C Pro's canister and twisting the canister into place, pull the trigger and begin the recharge. Shake and rotate the can while charging, and periodically stop and check the pressure level to avoid overcharging. You may notice that the can will get extremely cold while recharging, so maybe wear gloves while doing this.

The A/C Pro's pressure gauge features a rotating overlay that should let you estimate the proper pressure level. With the center of the red "V" shape pointed at the ambient temperature, fill the system until the level falls between the two red lines.

With the system recharged, I remeasured the temperature of the air blowing through the system. The new 64-degree Fahrenheit reading was 20 degrees lower than the initial temperature.