Modern Refrigeration and Air Conditioning 18th Edition Andrew D. Althouse

Textbook introducing the principles of air conditioning and refrigeration. Contains all of the most recent technology and EPA rules, with a standard coding scheme and maximized readability. 

Advanced Engineering Mathematics, 7th Edition by Peter V. O'Neil

A revision of the market leader, Peter V. O’ Neil is known for its comprehensive coverage, careful and correct mathematics, outstanding exercises, helpful worked examples, and self-contained subject-matter parts for maximum teaching flexibility.