Phone: 415-398-5202 Fax: 415-541-9175       Business Hours: Monday - Friday 7:30 AM - 4:30 PM (Emergency Calls)               Valerie Howerton President valerie@columbiamechanical.com     Vince Howerton General Manager vince@columbiamechanical.com     Wayne Howerton VP & Sr. Estimator/PM wayne@columbiamechanical.com     John Gumba Estimator/Project Manager john@columbiamechanical.com     Tommy Kong Estimator/Project Manager tommy@columbiamechanical.com     Henry Jones Assistant Estimator/Project Manager henry@columbiamechanical.com     Edward Dizon Assistant Project Manager edward@columbiamechanical.com     Quint Jear Sheet Metal General Foreman quint@columbiamechanical.com     James Gilmore Sheet Metal Foreman james@columbiamechanical.com     Fil Tringali Plumbing General Foreman fil@columbiamechanical.com     Dennis Pintarelli Plumbing Foreman dennis@columbiamechanical.com     Brandon Dill Service Foreman brandon@columbiamechanical.com     Kristine Lo Office Manager kristine@columbiamechanical.com     Anna Liu Accounting Assistant anna@columbiamechanical.com