With the HVAC industry rapidly moving away from R-22 due to environmental regulations and production phase-outs, technicians and facility owners alike are seeking reliable alternatives that minimize cost and disruption. One of the most popular and field-tested choices is R-438A, also known as MO99. Manufactured in the USA by Chemours and available in convenient 25 lb cylinders, R-438A is trusted by professionals as a dependable drop-in replacement for legacy R-22 systems.

Whether you’re managing a commercial building, performing routine maintenance, or sourcing refrigerant in bulk for HVAC servicing, understanding the benefits of R-438A (MO99) can help you make an informed choice. In this guide, we’ll explore what makes this refrigerant so effective, how it compares to other R-22 replacements, and why Chemours remains a top manufacturer in the industry.

Understanding R-438A (MO99): A Drop-in R-22 Alternative

R-438A (marketed as MO99) is a non-ozone-depleting hydrofluorocarbon (HFC) blend engineered by Chemours (formerly DuPont) to serve as a direct replacement for R-22 in existing air conditioning and refrigeration systems.

This refrigerant is designed for use in:

➾ Residential air conditioners
➾ Commercial rooftop systems
➾ Supermarket refrigeration
➾ Walk-in coolers and freezers
➾ Industrial process chillers

Unlike other R-22 replacements that require an oil conversion or component change-out, R-438A can be used with the existing mineral oil, alkylbenzene, or POE oils already present in most systems — reducing the need for system downtime or extensive retrofits.

Why Choose the 25 lb Cylinder Format?

The 25 lb cylinder is a popular packaging option for HVAC professionals. It offers:

➾ Convenient handling and transport
➾ Ideal volume for single or multiple system recharges
➾ Easy storage on service trucks or in supply rooms

When sourced from trusted distributors, such as RoyalRefrigerants.com, these cylinders ship the same business day, helping reduce project delays and meet tight deadlines.

Key Benefits of R-438A (MO99) Refrigerant

1. No Oil Change Required

One of MO99’s standout advantages is that it can be used with existing lubricants, including mineral oil. This means you can skip the time-consuming oil flush that’s often required with other replacements like R-407C.

2. Broad Equipment Compatibility

From air conditioners and refrigeration units to cold storage facilities and walk-in freezers, MO99 works across a wide variety of applications. It’s rated for use in both low and medium-temperature systems.

3. Performance That Matches R-22

R-438A provides similar cooling capacity and energy efficiency to R-22, ensuring the same level of comfort and performance your customers are used to. In many cases, systems retrofitted with MO99 maintain optimal temperature control without significant adjustment.

4. Environmentally Friendly

With zero ozone depletion potential (ODP), MO99 is a responsible choice for eco-conscious facilities. It also complies with EPA regulations under the Clean Air Act.

How to Retrofit Your System to R-438A (MO99)

Retrofitting an R-22 system to use R-438A is a straightforward process when done correctly. Here's a typical retrofit workflow:

Step 1: System Evaluation

☛ Inspect the system for leaks or worn-out components.
☛ Ensure system capacity is appropriate for MO99’s specifications.

Step 2: Recover R-22

☛ Use approved recovery equipment to safely remove all remaining R-22 refrigerant from the system.

Step 3: Replace Components if Needed

☛ Replace the liquid line filter-drier.
☛ Inspect or replace seals and gaskets that may be incompatible with HFCs.

Step 4: Charge with R-438A

☛ Add R-438A refrigerant in liquid form.
☛ Monitor superheat and subcooling to optimize performance.

Step 5: Label and Document

☛ Clearly label the system with MO99 identification.
☛ Record pressures, temperatures, and performance data for future reference.

Important Note: Never mix R-22 and MO99 in a system.

Chemours: Trusted Manufacturer of R-438A Refrigerant

Chemours is a recognized leader in refrigerant innovation. Their R-438A (MO99) formula is manufactured in the USA with high purity and consistent composition. Choosing Chemours ensures:

→ Quality you can trust
→ Reliable performance data
→ Full compliance with environmental regulations
→ Support from a global manufacturer

When sourcing refrigerant for mission-critical cooling systems, brand reputation matters. Chemours’ long-standing legacy, dating back to DuPont, makes it one of the most trusted names in refrigeration.

R-438A vs. Other R-22 Replacements

With several R-22 replacements on the market, it’s helpful to understand how MO99 compares.

MO99 stands out for its combination of drop-in compatibility and performance, especially for systems where oil change is undesirable or impractical.

Same Business Day Shipping Makes a Big Difference

Time is money in the HVAC world. That’s why companies like Royal Refrigerants offer same business day shipping on R-438A (MO99) 25 lb cylinders. When you need refrigerant fast — for emergency repairs, hot-season demand, or inventory restocking — having access to fast fulfillment can be the difference between a job done on time and a missed deadline.

Benefits of buying from trusted online refrigerant distributors:

→ Fast order processing
→ Secure checkout
→ Bulk discount pricing
→ Real-time tracking
→ USA-based customer support

Frequently Asked Questions About R-438A (MO99)

Q: Can R-438A be used in all R-22 systems?

A: Yes, it is designed for use in most R-22 systems including residential AC units, supermarket refrigeration, and commercial chillers.

Q: Is an oil change required when switching from R-22 to MO99?

A: No. R-438A is compatible with mineral oil, alkylbenzene, and POE oils.

Q: Can I mix R-438A with R-22?

A: No. Mixing refrigerants can lead to poor system performance and equipment damage. Always perform a full evacuation before charging with R-438A.

Q: How long does a 25 lb cylinder last?

A: This depends on the size and type of the system being serviced. A 25 lb cylinder is typically sufficient for multiple system recharges.

Q: Where can I buy R-438A refrigerant online?

A: You can order directly from Royal Refrigerants, which stocks Chemours MO99 in 25 lb cylinders and offers same day shipping.

Final Thoughts: Why R-438A (MO99) Is a Smart Long-Term Solution

The phase-out of R-22 isn’t just a regulatory issue — it’s a business opportunity to optimize your cooling systems with long-term, sustainable solutions. With R-438A (MO99) from Chemours, professionals get:

✔ The convenience of a drop-in replacement
✔ No oil change required
✔ Proven performance and reliability
✔ Fast nationwide shipping
✔ Support from a trusted U.S. manufacturer

Whether you’re a technician, distributor, or facility manager, transitioning to MO99 can help you protect your systems, your budget, and the environment — without sacrificing cooling performance.

🔗 Ready to Upgrade Your HVAC Systems?

👉 Order R-438A (MO99) 25 lb Cylinder from Royal Refrigerants — and enjoy same-day shipping, competitive pricing, and expert service from HVAC pros you can trust.