134a Charging Chart

As an air-conditioning refrigerant in newer automobiles, the optimal running pressure for R134A is between 22 and 57 pounds per square inch.

What should the high and low side pressures be for 134a?

Ambient Temperature (°F)	Low Side	High Side
85°	50-55 psi	220-250 psi
80°	45-50 psi	175-220 psi
75°	40-45 psi	150-175 psi
70°	35-40 psi	140-165 psi

What is the suction and discharge pressure for R134A?

The boiling temp of R134A is -15 degrees F at 1 bar absolute pressure. If the designer of the unit wanted to achieve -10F in the freezer case, they would design for 2 or 3 PSIG on the suction side at that cabinet temperature. They could design for -15F and run the suction to 0 or -5PSI, but that is a bad situation.

How do you charge R134A refrigerant?

1. Step 1: Turn On Your Car and A/C.
2. Step 2: Locate Your Low-Pressure Port and Attach Your Gauge. ...
3. Step 3: Check the Compressor Clutch to See If It's Engaging. ...
4. Step 4: Test Your A/C System Pressure. ...
5. Step 5: Disconnect The ZeroR® R134a AC Refrigerant Top Off Kit.

What happens if you overfill R134a?

Having too much refrigerant in your AC can damage the compressor. This can happen because the excess refrigerant will likely collect inside the compressor and cause subcooling, wherein temperatures are below normal. Furthermore, the extra refrigerant can flood the compressor and damage its mechanical parts.

What is the right amount of refrigerant to charge?

Charge liquid refrigerant into the high side of the system. Weighing the charge is recommended with the initial charge consisting of approximately 2.5 pounds per system ton.

What happens if refrigerant pressure is too low?

Low refrigerant means low pressure and low pressure means low temperatures that will eventually freeze something called an evaporator coil. When the evaporator coil freezes, cold liquid refrigerant flows through the refrigerant line, causing the surrounding moisture in the air to freeze.

What should the high and low side pressures be?

The pressure reading from the low side should be between 25 and 30 psi and the high side between 200 and 250 psi. But if you see the AC low side high, high side low, such as the low side is 100 and the high side is 150, there might be problems with any of the inner components.

Do you charge AC on high or low side?

Every auto air conditioning system has two service ports: one on the high pressure and one on the low pressure side. When recharging with AC Avalanche refrigerant, for safety, you will charge through the low side service port. Never charge through the high side port.

Do you charge R134a in vapor or liquid?

Being a pure refrigerants, R134a, R12 and R22 can be charged either way. The blends like R401A, R409A, R410A and all in the 400 series of refrigerants must be charges as a liquid. The Azeotropes in the 500 series like R502 and R507 act nearly like pure refrigerants and can be charged either way as well.

What happens if suction pressure is high?

Problems Caused By High Suction Pressure The condenser coil may struggle to release heat stored within the refrigerant. Your AC system may still turn on, but if it has high suction pressure, it may not provide sufficient cooling power. High suction pressure can lower the cooling power of your AC system.

What is normal suction pressure?

The normal range of the suction pressure is 0.8–1.2 MPa. If the suction pressure is greater than 1.2 MPa, connect a rubber hose for the pressure gauge to the gas pipe needle valve for the outdoor unit, and rotate open the pressure gauge to slowly release refrigerant. Start the compressor.

How do I know if I overcharged AC?

4 Signs Of An Overcharged Air Conditioning System

1. Higher Cost of Operation. An overcharged air conditioner system costs more money to operate, by decreasing overall efficiency.
2. Sticky Indoor Air. ...
3. Excessive Condenser Heat. ...
4. Non-Functioning Air Conditioner.

What happens if you charge AC on high side?

The damage from trying to charge on the high side would be to you - not the system. More than likely the pressure would back up into the can and explode it like a grenade. If you don't know what you're doing, seriously get someone to help out. You ALWAYS want to connect to the low side.

Do you need to vacuum AC before recharge?

The air needs to be evacuated to remove not only the air (which makes a lousy refrigerant), but also the water vapor in the air. Yes, you need to add the proper amount of oil. But you need to drain the old oil first to ensure you don't end up with too much.

How do I know if my refrigerant is full?

Simply remove the cap from the port and push the coupler onto the port. Make sure the can of freon is disconnected when testing your freon level. While pressure is engaged, at this point you will take your reading. Use the gauge that is attached to the hose to find out how much freon is in your AC unit.

Is it illegal to vent R134a?

R134a is not an ozone-destroying agent, but it is a greenhouse gas, and is illegal to vent as well.

Why is my AC still not cold after recharge?

Numerous reasons can cause the compressor to not to connect with the vehicle AC. It could be an electrical failure in the circuit during charging, overheating vehicle, or maybe the coolant is just low.

What are symptoms of low refrigerant charge?

7 Signs Your AC Unit is Low on Refrigerant

• It takes a long time for your home to cool off.
• Vents are not blowing cool air. ...
• The temperature you set is never reached. ...
• Your electric bill is higher than normal. ...
• Ice on refrigerant lines. ...
• Water leaking around heater. ...
• Hissing or bubbling noise.

Is 2 lbs of refrigerant a lot?

The rule of thumb is two to four pounds of refrigerant per one ton of your unit. You should always check the specifications of your unit. However, most home air conditioning units are between one ton and five tons. Anything over five tons is considered a commercial grade unit.