Hours Of Operations ADT California Monrovia ADT Hours of Operation and Locations in Monrovia, CA 4.7 - 140 votes 2 Locations in Monrovia www.adt.com ADT Hours Category: Home & Garden ADT - Monrovia, CA 91016 623 S Myrtle Ave(626) 605-0008 View Store Details ADT - Monrovia, CA 91016 (626) 873-2328 View Store Details Explore MonroviaView More Apparel MarshallsRoss Dress for LessCarter'sKohl's OutletTalbots Sports 24 Hour FitnessG's Fashion Jewelry MarshallsKohl's OutletAvon Recommend For You Stacy Furniture Build-A Bear Workshop J. C. Penney 84 Lumber A.C. Moore Arts & Crafts Adams Golf American Standard American TV & Appliance Andersen Windows & Doors Andronico's Market