2019 International MV A/C Refrigerant & Oil

Quick Answer

• Refrigerant Type: R-134a (most common for this class of vehicle, though R-1234yf may be found on some later or specialized models. Always check the underhood label.)
• Full System Charge: 54-58 oz (1530-1640 grams) – Always refer to the underhood A/C system label for exact specifications.
• PAG Oil Type: PAG 46
• PAG Oil Amount: 8-10 fl oz (235-295 mL) – Varies by system configuration and component replacement.
• Low-Side Service Port Location: On the larger diameter A/C line, typically near the accumulator/drier or close to the firewall on the passenger side.
• High-Side Service Port Location: On the smaller diameter A/C line, usually between the condenser and the firewall, often closer to the compressor or manifold.

Why R-1234yf Matters (and Why Your MV Likely Has R-134a)

While passenger vehicles transitioned to R-1234yf refrigerant around 2014 due to its lower Global Warming Potential (GWP), heavy-duty trucks like the International MV often adopted this change more slowly, or sometimes not at all, especially for the 2019 model year. R-134a was still widely used due to its proven reliability and lower cost.

Understanding the specific refrigerant in your 2019 International MV is critical. R-1234yf is significantly more expensive, requires specialized recovery and recharge equipment, and is not compatible with R-134a systems. Mixing refrigerants can cause severe damage to your A/C system components and recovery equipment. Always verify the refrigerant type on your underhood A/C label.

Recharge Procedure (Critical Considerations)

Recharging an A/C system isn't as simple as just adding refrigerant until the pressures look right. For an International MV, and indeed any modern A/C system, precision is paramount. Overcharging or undercharging can both lead to poor cooling performance and premature component failure.

1. Evacuation is Key: Before adding any new refrigerant, the system must be evacuated using a vacuum pump. This removes all air and moisture, which are non-condensable and corrosive, severely degrading system performance and longevity.
2. Charge by Weight, Not Pressure: The most accurate way to charge an A/C system is by weight, using a precise charging scale. The recommended charge weight for your MV will be on the underhood label. Using pressure gauges alone to determine the charge can be misleading due to varying ambient temperatures and humidity.
3. Correct PAG Oil: If any components were replaced, ensure the correct PAG 46 oil is used and added in the specified amount. Too much or too little oil can lead to compressor failure.

Common A/C Problems for the International MV

Heavy-duty vehicles like the International MV operate under demanding conditions, leading to specific A/C system challenges:

• Compressor Failures: Often due to contamination from system breaches, improper lubricant, or continuous operation with low refrigerant causing overheating.
• Condenser Issues: Located at the front of the vehicle, condensers are susceptible to damage from road debris and corrosion from road salt. Reduced airflow due to debris blockage can also hinder its efficiency.
• Evaporator Leaks: Over time, vibrations and temperature cycles can cause leaks in the evaporator coil, often manifesting as a musty smell and reduced cooling. These are usually labor-intensive to repair.
• Hose and Fitting Leaks: High pressures and vibrations can cause O-rings, hoses, and fittings to degrade and leak. These are often easier to diagnose and repair.

When to Call a Pro

While adding a can of refrigerant might seem simple, correctly diagnosing and repairing an A/C system requires specialized tools, training, and knowledge of refrigerant handling procedures. If you notice any of these symptoms, it's time to call a professional:

• No cold air or inconsistent cooling.
• Unusual noises from the engine bay when the A/C is on.
• Visible leaks, especially around A/C components.
• Frequent need to "top off" refrigerant.

Safety Disclaimer: Working with automotive refrigerants requires proper training and certification. Refrigerants can cause frostbite on contact and are harmful if inhaled. It is illegal to intentionally vent refrigerants into the atmosphere. Only EPA 609 certified technicians should perform A/C service.

Find a certified A/C shop on Repairius.