No r22 is being phased out, the dates varie from country to country, but is already hard to get in some places
No.
Most new equipment is built for and charged with R410a, a refrigerant with much higher pressures than the R22 used for decades, R22 units are still available, dry charged however, you must fill them with R22 onsite. This is how new R22 compatible equipments being sold still.
R22
R22
R22 r123
r22
R22
R22
No, refrigerants cannot be blended.
if approved by the compressor manufacturer, then yes, if not, then no...
No
ef22a is a refrigerant. It is used in place of R22. It is a Hydrocabon refrigerant. Very efficient.....