What certification is required to repair a chiller operating with R-22?

To repair a chiller operating with R-22 refrigerant, one must obtain Type II certification. This certification is specifically focused on high-pressure refrigerants, which includes R-22, a chlorofluorocarbon (CFC) that is categorized as a high-pressure refrigerant.

Type I certification is relevant for servicing small appliances, which typically do not involve high-pressure systems. Type III certification pertains to low-pressure refrigerants, which are different from those classified under Type II. There is also a misunderstanding in the answer choice, as no certification is indeed required for low-impact refrigerants or simple repairs, but for R-22, Type II is necessary due to the specific regulations associated with handling CFCs.

Thus, Type II certification is mandated for technicians who work with high-pressure systems like those using R-22, ensuring they possess the knowledge and skills required to handle these refrigerants safely and in compliance with Environmental Protection Agency (EPA) regulations.