How to To Read an R134

Air conditioning gauges such as the R134 help you know how much is left in your conditioner.

R134a is a type of air conditioning fluid that is used in cars. The R134 gauge lets you know how much of the coolant is left in your conditioner. It is a gauge that must be inserted into your coolant system hose. Reading the gauge is necessary from time to time so that you have enough of the coolant left in the car. The gauge can help alert you if coolant is escaping faster than normal or if you need to replace your coolant for it to work properly.

Things You'll Need

• R134 gauge

Instructions

1. Turn the valve handle on the gauge counterclockwise until the small gauge stem comes out all the way. Wait for the needle to “click” before you stop turning it.

2. Find your air conditioning system and look for the service port. Take the cap off of the port and set the cap to the side.

3. Fit the hose from the gauge over top of the service port. Push the small piercing needle at the end of the hose into the hole in the center of the port.

4. Screw the end of the hose clockwise on the service port to attach it to the service port. Tug the hose lightly to make sure it is attached.

5. Turn on your car and run the air conditioner at the “Max A/C” setting and the fan speed on “High.” Run it for about two to three minutes with your engine running below 1,500 RPM.

6. Look at the gauge while the car is running to see how much R134 is left in the car. If the needle points in the green, you have enough R134. If the needle is in the yellow, you may need to add R134 in a few months. Immediately add more R134 if the needle is in the red.

References

• Central Air Conditioner and Refrigeration: HVAC Gauges
• Drive Green: R134a Check and Charge Hose