SC Refrigeration Practice Questions - South Carolina Refrigeration Contractor Examination Exam

No purge is required if the tube is new Pre-purge for a minimum of five volume changes at not less than 100 ft/min, then maintain 1.0 to 3.0 psi of inert gas during brazing; filler metal shall conform to AWS A5.8 Fill the pipe with oxygen at 15 psi to keep the joint hot Use only shop compressed air because it is already dry