Dear All, The refrigerant piping are made of copper, it is advisable to change the pipe when you change the Air Conditioning system. It is because the moisture or foreign particles may contain within the piping: that will harmful to the compressor, and also, the refrigerant gas are not approved type if installed years ago. Sometimes because the pipe are concealed on the wall, it is very difficult and time consuming to change the pipe, so the contractor will suggest not to change. For proper method of installing the piping, the chipping particles shall be clear away form the pipe, Blow the pipe with nitrogen gas; connect the pipe to the condenser coupling joint, Vacuum the pipe system with nitrogen gas while shut off the valves inlet N outlet to the compressor. The charge in the refrigerant gas of R-410 as approved by the Authority.
