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Hello, you can do it, but the R-22 coil will be leak prone, especially if its older. R 410a runs at roughly twice the pressure that R-22 does,
You will also have to flush any of the mineral oil from the R22 evaporator, mineral oil tends to form clots when mixed with the oil used in R410a systems (POE, Polyol Ester Oil, an organic oil). You can buy a refrigerant flush kit from your local refrigeration wholesaler.
You will also need to change the refrigerant metering device to match your R410a system.
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