| 1-877 Appliance Repair INC | Ayriyan Gary | 1877appliance@gmail.com | (858) 222 9542 | HVAC | La Mesa · San Diego County | — | — |
| 1800 Anytime Plumbing Heating & Air | Geno Anthony Gruber | — | (800) 269 8463 | HVAC | Coronado · San Diego County | — | — |
| 1st Choice Plumbing Heating And Air | Fernando Andres Jr Rojas | — | (760) 696 1201 | HVAC | Oceanside · San Diego County | — | — |
| 1st Response Plumbing & Flood Damage | Robert Damien Cervantes | jared@1stresponseplumbing.com | (858) 203 0930 | HVAC | National City · San Diego County | — | — |
| 24/7 Drain Rooter INC | James Norman Padgett | interested@domainmarket.com | (619) 303 3575 | HVAC | El Cajon · San Diego County | — | — |
| 3 - D Enterprises Incorporated | Elihu Shahrokh | office@3d-nt.com | (858) 530 2202 | HVAC | San Diego · San Diego County | — | — |
| 4 M Mechanical INC | Michael Anthony Foutch | — | (619) 944 4822 | HVAC | San Diego · San Diego County | — | — |
| 5 S Contracting INC DBA Landmark Mechanical | Gary Ray Seelinger | — | (858) 279 1222 | HVAC | San Diego · San Diego County | — | — |
| 5 Star Mechanical INC | Aleksei Geringer | — | (619) 766 5520 | HVAC | San Diego · San Diego County | — | — |
| 619 Heating And Air | 619 Heating And Air | — | (619) 616 5538 | HVAC | Chula Vista · San Diego County | — | — |
| A & B Air Conditioning & Heating | Jaclyn Michelle Bowman | info@aandbairconditioning.com | (619) 596 0653 | HVAC | Santee · San Diego County | — | — |
| A / C Mechanical Sol INC | Bozickovic Mladen | — | (858) 733 1534 | HVAC | San Diego · San Diego County | — | — |
| A Air Heating And Air Conditioning | Faris Fuad Arabo | — | (619) 922 2442 | HVAC | El Cajon · San Diego County | — | — |
| A C & H Mechanical Corp | Millan Conrrado Albarran | info@achmechanical.com | (619) 864 0231 | HVAC | San Diego · San Diego County | — | — |
| A C Energy Systems INC | Maybeth Nolan Rothery | help@acesmonitoring.com | (760) 436 2116 | HVAC | Cardiff · San Diego County | — | — |
| A E Building INC | Estrada-bernal Alejandro | — | (888) 213 8453 | HVAC | Chula Vista · San Diego County | — | — |
| A G R Mechanical | A G R Mechanical | — | (619) 977 0271 | HVAC | San Diego · San Diego County | — | — |
| A O Reed & Co LLC | Steven Brent Andrade | info@aoreed.com | (858) 565 4131 | HVAC | San Diego · San Diego County | — | — |
| A&r Mechanical INC DBA A&r Building Solutions | Alberto Arturo Nunez | — | (619) 302 5959 | HVAC | Escondido · San Diego County | — | — |
| A+ Air Comfort Solutions INC | Gabriel Dominick Rodelo | mn@tritonair.net | (760) 938 6165 | HVAC | Escondido · San Diego County | — | — |
| A/c Doctors Tv INC | Larry Dean Morrow | — | (760) 566 9335 | HVAC | Oceanside · San Diego County | — | — |
| Aaa Quality Heating And Cooling INC | Ali Afif Mjeed Anaee | — | (619) 404 8254 | HVAC | Oceanside · San Diego County | — | — |
| Aair Tech Refrigeration & A / C INC | Yousif Steve | — | (619) 250 2326 | HVAC | La Mesa · San Diego County | — | — |
| Abc Heating & Air | Robert Charles Sanford | — | (619) 599 8223 | HVAC | San Diego · San Diego County | — | — |
| Abc Heating & Air Conditioning | Abc Heating & Air Conditioning | — | (619) 504 8116 | HVAC | Lakeside · San Diego County | — | — |
| Abc Plus | Abc Plus | — | (858) 864 4789 | HVAC | Chula Vista · San Diego County | — | — |
| Able Heating & Air Conditioning INC | Moses Nathaniel Moreno | steved@precision-ac.com | (619) 409 9100 | HVAC | Chula Vista · San Diego County | — | — |
| Abm Building Services LLC | Richard John Cooke | — | (858) 279 1300 | HVAC | San Diego · San Diego County | — | — |
| Absolute Air | Absolute Air | mn@tritonair.net | (760) 731 7600 | HVAC | Fallbrook · San Diego County | — | — |
| Absolute Duct & Chimney Cleaning Services | Sarah Kathryn Rotter | absolutedcc@gmail.com | (619) 328 9733 | HVAC | Santee · San Diego County | — | — |
| Absolute Plumbing Heating Air & Drains INC | Ramirez Lujano Jose Trinidad | micah@micahrich.com | (619) 862 0397 | HVAC | Chula Vista · San Diego County | — | — |
| AC Plus Construction | Robert John De Vries | mn@tritonair.net | (858) 254 7374 | HVAC | Poway · San Diego County | — | — |
| Accent Construction | Rodney Lamarr Thompson | info@accenteci.com | (619) 954 4852 | HVAC | Escondido · San Diego County | — | — |
| Accord Air INC | Oleg Pylypchuk | ahomeshvac@gmail.com | (858) 282 3358 | HVAC | Escondido · San Diego County | — | — |
| Ace Contractors | Mark Lawrence Allen | jlvplumbing82@yahoo.com | (858) 925 5400 | HVAC | San Diego · San Diego County | — | — |
| Ace Contractors | Jill Beth Carrozzo | — | (760) 801 9070 | HVAC | San Marcos · San Diego County | — | — |
| Ace Coolers INC | Michael Edward Turner | — | (858) 541 2623 | HVAC | San Diego · San Diego County | — | — |
| Ace Group Ki LLC | Imran Jaffer | aqremodeling2@gmail.com | (703) 870 5360 | HVAC | San Diego · San Diego County | — | — |
| Acman Quality HVAC INC | Guadalupe Rodolfo Alfaro Zurita | info@acmanqualityhvac.com | (858) 280 5483 | HVAC | Vista · San Diego County | — | — |
| Acp Air Conditioning Professional | Acp Air Conditioning Professional | steved@precision-ac.com | (619) 796 1986 | HVAC | Chula Vista · San Diego County | — | — |