Generally not, although in the case of split systems, the outdoor unit can be replaced with an R-410A unit following the manufacturer's guidelines. Care must be taken that the indoor coil is rated for the required R-410A burst pressure. This is also valid for all components which are installed in the system like pipes, accumulators, receiver, filter driers, TXVs, sight glasses, sensors etc., which must be approved for R410A operation. Because of the thermodynamic and pressure properties of R-410A, compressors were redesigned to properly match motors with displacement as well as meeting the higher shell burst pressure requirements. A compressor designed for R-22 would be overloaded and trip the motor protector if it were to pump R-410A at air conditioning conditions.

No, the same line sizes used for R-22 are used for R-410A. The ideal line size for R-410A is smaller in diameter than R-22 tubing and falls between the standard available nominal refrigerant tubing sizes. The same tubing sizes used for R-22 must be used for R-410A to avoid excessive pressure drops when using the next smaller tube.

If the second letter of the model number is a “P”, then the compressor is designated for R-410A. For example: ZP54K3E-XXX as opposed to the R-22 designation: ZR54KSE-XXX. Newly developed generations of R410A compressors may show the letter “P” in a different position.

A 100% molecular sieve drier should be used in any new system or system where no acid is present. Should non-organic acid be present, then a filter with 25% activated alumina may be installed.

The oil used in R-22 systems is either mineral-or semi-synthetic oil, the oil used in R-410A systems is a synthetic POE-oil. The need for additional oil depends on the application. Contact the OEM to find more information on additional oil charge.

Yes, moisture and contaminants:

• Moisture: Because Polyol Ester Oil (POE) absorbs moisture at a faster and higher rate than mineral oil, the time that the inside of the compressor can be exposed to the atmosphere is much shorter. Good practice dictates that the compressor plugs not be pulled until the compressor is set in place.
• System Contaminants: Polyol Ester Oil (POE) is an excellent cleaner and will carry copper-oxides and other contaminants, that mineral oil left in place, through the system, possibly clogging expansion devices. After the removal of the mineral oil and the recharge with POE oil the remaining mineral oil contents should not exceed 5 ppm. This can be easily determined with a refractometer. An inert gas, such as nitrogen, must be swept through the system to prevent copper-oxide formation during brazing.
• Both moisture and contaminant control should be normal procedures for R-22 installations and are even more important when installing a system with POE oil.

There are three distinct design differences between and R-22 and R-410A compressor:

• Different Oil: Because mineral oil, normally used in R-22 compressors, is not miscible with HFC refrigerants such as R-410A, Copeland uses a synthetic Polyol Ester Oil (POE) in R-410A approved compressors.
• Reduced Compressor Displacement: A pound of R-410A has approximately the same heat carrying capacity relationship to R-22 as R-22 has to R-12, therefore, the compressor displacement has to be reduced approximately 40% for a given motor horsepower. Using a compressor designed for R-22 to pump R-410A would overload the motor and cause protector trips.
• Higher Shell Burst Pressure Requirement: At any given saturated temperature, R-410A has approximately 60% higher pressure than R-22, which requires compressor shells to meet this higher pressure requirement.