R-407C Refrigerant: What It Is, What It Costs, and What to Do

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If your system’s label says R-22 but a service sticker says R-407C, your system was retrofitted at some point. That is a legitimate, EPA-recognized path for an R-22 system. It matters for you in two ways: a technician needs to know it is retrofitted before charging it, and a leak on a blend like this usually means recovering and re-weighing the full charge rather than adding a pound.

What is R-407C?

R-407C is HFC blend (zeotropic), specifically 23% HFC-32 / 25% HFC-125 / 52% HFC-134a by weight. It is also sold and referred to as 407C, Suva 407C, Genetron 407C. Its ASHRAE Standard 34 safety classification is A1 — low toxicity, non-flammable, and its global warming potential is about 1,774.

Ozone depletion potential: zero. It is not an ozone-depleting substance.

What equipment uses it, and when was it common?

R-407C was common in residential equipment 2000 to the present. Used mainly as an R-22 retrofit refrigerant and in some legacy equipment. Not used in new US residential split systems.

Is it still used in new equipment?

No. New residential systems manufactured or imported from January 1, 2025 must use a refrigerant with a GWP under 700, and R-407C is above that limit.

Can existing systems still be serviced?

Yes. Existing R-407C systems can be serviced and recharged. Components used to repair existing systems are not restricted by the technology-transition rules, and there is no requirement for you to replace working equipment.

Is it compatible with other refrigerants?

Approved for use in R-22 equipment: yes. Approved for use in R-410A equipment: no.

The most common R-22 retrofit. Because it is a zeotropic blend with significant temperature glide, it must be charged as a liquid, and a leak cannot simply be topped off without changing the blend’s composition. A retrofit normally also means changing to POE oil.

Never assume two refrigerants are interchangeable because their pressures or performance look similar. Compatibility is a property of your specific equipment, established by its manufacturer, not a property of the refrigerant alone.

What does it cost?

We do not track a separate installed price benchmark for R-407C. It is a retrofit refrigerant rather than a routine stock item, so pricing varies more than for the mainstream refrigerants and is best quoted directly.

Why does service cost more than the refrigerant?

Blend fractionation means a proper repair often means a full recover-and-recharge rather than a top-off, so the labor and refrigerant quantity are both higher.

Beyond that, every refrigerant invoice carries a licensed technician’s time, EPA Section 608 certification, recovery and evacuation equipment, refrigerant carried as truck stock, insurance, and a warranty on the work. The quote checker breaks a real invoice into those parts.

How much might a residential system contain?

As a planning estimate, a typical residential system holds roughly 2 to 4 pounds per ton of cooling capacity — about 6 to 12 pounds for a common 3-ton system. That is an estimate, not a specification: actual charge depends on the indoor coil match and the line set. Estimate your own system.

How to tell if your system was retrofitted

Look for a service sticker near the original nameplate. A proper retrofit is supposed to be labeled, because the next technician needs to know what is actually inside. If the nameplate says R-22 and a sticker says R-407C, the sticker wins.

If there is no sticker and you suspect a retrofit, say so before any work starts. A technician charging the system as though it were R-22 will not get the right result.

Why a leak is handled differently on a blend

R-407C is a zeotropic blend of three components with meaningful temperature glide, which has a real consequence: when it leaks, the components do not leave in equal proportion. The refrigerant remaining in the system is no longer the blend it started as.

That is why a blend like this is charged as a liquid, and why a proper repair usually means recovering the remaining charge and weighing in a fresh full charge rather than topping off. It costs more in both labor and refrigerant, and it is the correct way to do it rather than a padded invoice.

What should you ask your technician?

• Can you show me where R-407C is listed on my equipment?
• What is the expected total charge for this model?
• How much are you adding today, and was the system weighed?
• Where do you think it leaked from, and did you perform a leak search?
• Is the leaking component under manufacturer warranty?

All 20 questions, grouped by when to ask them →

When does repair versus replace become the real question?

When the repair is a large share of replacement cost, when the equipment is past roughly 12 years, or when the leaking component is a coil or compressor outside warranty. A refrigerant phase-down on its own is not a reason.

Work through the repair-or-replace decision →

Related: Refrigerant hub · Find my refrigerant · Refrigerant timeline · AC repair vs replace

Frequently asked questions

My AC label says R-22 but the sticker says R-407C. Which is right?

The service sticker. The nameplate records what the equipment was built with; the sticker records that it was retrofitted. Tell any technician about it before they work on the system.

Is a R-407C retrofit as good as the original R-22?

Usually slightly less capacity and efficiency than the system had on R-22 when new. It is a legitimate way to keep an R-22 system running, but it is a compromise rather than an upgrade.

Why can’t a R-407C system just be topped off?

It is a zeotropic blend whose components leak at different rates, so what remains after a leak is no longer the original mixture. Adding more does not restore the correct composition, which is why a proper repair recovers and weighs in a full fresh charge.