PPI HVAC and Refrigeration Six-Minute Problems – Comprehensive Practice Problems for the NCEES PE Mechanical HVAC & Refrigeration Exam

PPI HVAC and Refrigeration Six-Minute Problems – Comprehensive Practice Problems for the NCEES PE Mechanical HVAC & Refrigeration Exam

PE Mechanical Engineering: HVAC and Refrigeration Practice Exam

PPI PE Mechanical HVAC and Refrigeration Practice Exam, 2nd Edition – Comprehensive and Realistic Practice Exam for the PE Mechanical HVAC and Refrigeration Exam