When replacing R12 with R134a, you should initially charge the system with about 75% to 85% of the original R12 factory capacity.
Converting an R12 air conditioning system to R134a is possible, but it requires a full retrofit. Because R134a operates at higher pressures and uses different oil, you must evacuate the old refrigerant, flush the system, replace the O-rings, install a new receiver-dryer, change the oil, and add service port adapters.
The most common and practical replacement for R12 (Freon) in automotive and stationary systems is R134a. However, switching from R12 to R134a requires retrofitting, which involves replacing the system's O-rings, accumulator/drier, and flushing the old mineral oil out for a compatible PAG or POE synthetic oil.
Does R12 blow colder than R134? Yes it does. In very simple terms, since R134A operates at a higher pressure it moves through the condenser faster so it does not have time to dissipate heat.
However, R134a is not a 'drop-in' replacement for R12 because there is a need to change the compressor lubricant and expansion valve. Changing over from R12 to R134a can therefore be an ex-pensive and time consuming procedure.
R12 to R134a Charge Conversion Formula (pounds only)
Take the R12 charge specification and multiply it by 0.9. Then, subtract that result by 0.25 pounds to get the proper amount of R134a charge.
RS-24 is an easy-to-use Drop-in replacement for R12, There is no need to change the existing lubricant in the system, thereby avoiding a costly retrofit.
While the production of new R12 is banned, it is not illegal to sell or use R12. In fact, many of the cylinders and cans of Freon R12 sold for decades throughout the United States are still around today.
No, you should never mix R12 and R134a. Mixing these two refrigerants causes severe chemical and mechanical problems.
R-12 (also widely known by the trademarked name Freon) was phased out because it is a chlorofluorocarbon (CFC) that destroys the Earth's vital ozone layer.
When finding an R12 compatible refrigerant, the best choice depends on whether you are doing a full system conversion (retrofitting) or looking for a direct "drop-in" substitute. Here are the primary options:
RS-24 is a “Drop-in” alternative for R12 which also provides a long term solution at the same time.
Yes, R32 is not only currently available, but it is the primary EPA-approved replacement for older refrigerants like R410A in new ductless and mini-split air conditioning systems.
The amount of oil needed for an R12 to R134a conversion varies, but most users recommend using Ester oil and suggest amounts ranging from 4 to 8 ounces. "You must use ester oil for retrofitting an r12 system. PAG oil is NOT compatible with the original mineral oil. ... don't put more than 4 ounces in."
The best R12 to R134a conversion kits depend on what you need to replace. For a complete system retrofit (adapters, O-rings, and oil) check out the Old Air Products Retrofit Kit ($32.50). For a basic adapter swap, consider the FANOVO 90-Degree Adapter Kit (~$15).
R-134a officially replaced R-12 in automotive air conditioning systems following the 1994 model year, as automakers phased in the new refrigerant to comply with the federal ban on ozone-depleting chemicals. The production of R-12 was completely banned in the United States on January 1, 1996.
Converting an R12 air conditioning system to R134a is possible, but it requires a full retrofit. Because R134a operates at higher pressures and uses different oil, you must evacuate the old refrigerant, flush the system, replace the O-rings, install a new receiver-dryer, change the oil, and add service port adapters.
It takes ≈1.33is approximately equal to 1.33≈𝟏.𝟑𝟑 cans of 12 oz refrigerant to equal 1 pound.
In terms of sheer thermodynamic cooling efficiency, R12 is better. It transfers heat more effectively, operates at lower system pressures, and generally produces noticeably colder air. However, R12 is severely restricted and environmentally hazardous.
He said that a lot of people look to buy it and it could be well worth over $1000.
So carmakers were mandated to stop using R12 after the 1994 model year. One current replacement refrigerant is R134a - opens in new window or tab., which serves the same purpose as Freon but is less harmful to the environment. Freon is the well-known trademarked name for dichlorodifluoromethane gas.
A2L refrigerants, the new refrigerants for 2026, will replace R-410A in new systems. A lot about A2L refrigerants is explained in their name: The “A” means low toxicity. The “2L” is a safety classification, indicating it is mildly flammable.
R134a is a safer replacement for R12. Another major difference is the type of oil both refrigerators require. R12 is compatible with mineral oil, and most R12 systems use this. R134a uses Polyalkylene Glycol (PAG) oil.
Refrigerant can only be sold to technicians certified under the Section 608 or Section 609 technician certification programs, where individuals may only purchase refrigerant consistent with the appliances covered by their certification.
Yes, you can still buy R-12 refrigerant (Freon), but it is expensive (often exceeding $100 per pound) and strictly regulated. You cannot buy it in standard retail stores; it must be purchased through certified distributors or specialized secondary markets.