Ray Diestel founds Reliance Appliance in Oakland California. Initially he is a sewing machine repairman, but eventually expands the business to refrigeration along with heating and air conditioning. 

Diestel moves his family and the business to Chico, California. Reliance Appliance eventually settles in at 1710 Nord Ave now on highway 32. 

Robert (Bob) Wiley son-in-law to Ray Diestel sells his stake in a Dr. Pepper distribution center in San Leandro California. He moves his family to Chico. Eventually Bob learns the HVAC trade from his father-in-law and takes over Reliance Appliance. Bob receives his HVAC (C-20) & Refrigeration (C-38) contractors licenses in 1980.

Donald (Don) Wiley, Bob's son starts working on HVAC jobs with his dad at age 10. By the time he gets his driver license, Bob sends Don out on solo service calls.

Don receives his HVAC (C-20) contractors license and goes off on his own. He later incorporates Dr. Heating and Air in Oroville, California. Overtime Don also earns his Refrigeration (C-38) & Electrical (C-10) Licenses. 

Don sells Dr. Heating & Air to Endeavor Homes. He eventually decides to pursue an education in electrical engineering at CSU Chico. Don works for notable employers such as NAVAir & U.S. Steel. On the side he builds Comfort Zone Heating & Air in 2015 and eventually takes on customers from Reliance Appliance after Bob Wiley's retirement.

Joseph Mackey, Don's son-in-law starts learning the HVAC trade on the side. He eventually takes on a strong interest in continuing the family business. 

After Don's experience as an electrical engineer  and Joseph working on finishing his MBA at Sac State, both decide to take the family sole proprietorship to the next level and create Comfort Zone Enterprises, Inc.