About Us

Tetra Heating and Air Conditioning’s journey started in 1968 out of the trunk of a 1962 Ford Falcon and went by the name of Sentinel Refrigeration headed by Mike Donnelly. In 1971 we became a C-38 specialty contractor and in 1995 added C-20 when Kent Donnelly took ownership. In 2011 we changed our name to Tetra Mechanical still installing high performance, safe, comfortable and efficient air comfort packages for families and businesses.

Heading onto 3 Generations Kent’s youngest Son Jeffery apprenticing with Kent is gaining ground learning aspects of service, maintenance and air balancing.

Kent’s daughter Melesia, met and Married Mike Perez. Mike joined Tetra proving to be an invaluable talent. Mike is now Vice President of Construction. Mike holds several certifications including welding, duct optimization, duct performance, system performance.

Sometime later after managing and growing a catering company Melesia joined Tetra and now manages the office, oversees accounting and is Executive Assistant. Having a work ethic that is not matched by any other, thus keeping you and your family safe & comfortable.

Being in the industry for so many years we had the privilege working for or on projects to notables such as, a US President, many Hollywood Stars, Fortune 100 Companies, Iconic structures throughout Los Angeles, LEED Buildings with Certification of Gold, Platinum, attractions such as Magic Mountain, Disney, Universal Studios, Ronald Regan Library and Industrial buildings like mega Giant Kroger Foods, and Hugh’s Air Craft but your home is most important to us with 3 Generations, our family, looking out for your family.

Welcome to Tetra. Welcome Home.