| S. ON AIR-CONDITIONING COMPANY LIMITED | | Live |
| Hon Kai Air-conditioning Company Limited | | Live |
| Accel Air-conditioning Limited | Private company limited by shares | Dissolved |
| Airwell Air-conditioning (Asia) Company Limited | Private company limited by shares | Live |
| Airwell Air-conditioning (Hong Kong) Company Limited | Private company limited by shares | Live |
| ALLIANCE AIR-CONDITIONING COMPANY LIMITED | Private company limited by shares | Dissolved |
| ANCAPRO AIR-CONDITIONING MACHINERY ENGINEERING LIMITED | Private company limited by shares | Live |
| ARNLEE AIR-CONDITIONING LIMITED | Private company limited by shares | Live |
| TAK LEE AIR-CONDITIONING (ASIA) LIMITED | Private company limited by shares | Live |
| AWIN AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| BEAULY AIR-CONDITIONING LIMITED | Private company limited by shares | Dissolved |
| WANG CHANG NAN AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Dissolved |
| WING CHEONG AIR-CONDITIONING PROJECTS LIMITED | Private company limited by shares | Live |
| CHEUK YUE AIR-CONDITIONING CO., LIMITED | Private company limited by shares | Live |
| CHIN MOK AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| EASTERN AIRCONDITIONING (CHINA) LIMITED | Private company limited by shares | Dissolved |
| TOP-AIRE AIR-CONDITIONING (CHINA) LIMITED | Private company limited by shares | Live |
| Topone Air-conditioning Engineering Co., Limited | Private company limited by shares | Live |
| XIAO XIONGMAO AIR-CONDITIONING CO., LIMITED | Private company limited by shares | Dissolved |
| CONCORD AIR-CONDITIONING COMPANY LIMITED | Private company limited by shares | Dissolved |
| Mr. Cool Air-conditioning Company Limited | Private company limited by shares | Live |
| WING LEE AIR-CONDITIONING ENGINEERING DESIGN LIMITED | Private company limited by shares | Live |
| BUILD IDEA ELECTRIC APPLIANCES & AIR-CONDITIONING LIMITED | Private company limited by shares | Live |
| WAI KEE AIR-CONDITIONING AND ELECTRICAL ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| NAM HOI ELECTRICAL & AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| Tak Kin Air-Conditioning & Electrical Engineering Co Limited | | Live |
| BRYLC AIRCONDITIONING & ELECTRICAL ENGINEERING COMPANY LIMITED | Private company limited by shares | Dissolved |
| YAU NGAI AIR-CONDITIONING ELECTRICAL ENGINEERING LIMITED | Private company limited by shares | Live |
| PROGRESSIVE AIR-CONDITIONING & ELECTRICAL LIMITED | Private company limited by shares | Dissolved |
| HOP KEE AIR-CONDITIONING & ENGINEERING COMPANY LIMITED | Private company limited by shares | Dissolved |
| HO YUE AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| KIN YIP AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| YAU LEE AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| KIN WAI AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| TAK LEE AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Dissolved |
| FOR TIN AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| TAT LEE AIR-CONDITIONING AND ENGINEERING LIMITED | Private company limited by shares | Live |
| TIN LOK AIR-CONDITIONING & ENGINEERING LIMITED | Private company limited by shares | Live |
| MAN KEE AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| PAK KEE AIR-CONDITIONING ENGINEERING CO. LIMITED | Private company limited by shares | Live |
| SUN FAI AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| YUK FAI AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| HON FAI AIR-CONDITIONING ENGINEERING CO. LIMITED | Private company limited by shares | Live |
| YKC AIR-CONDITIONING & ENGINEERING LIMITED | Private company limited by shares | Live |
| WUI TAT AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| SUN KEE AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| PAK YIN AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| WAI YIP AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| Wan Ho Air-Conditioning Engineering Company Limited | Private company limited by shares | Live |
| YAU YU AIR-CONDITIONING ENGINEERING LIMITED | | Live |
| NEW KIN YIP AIR-CONDITIONING ENGINEERING COMPANY LIMITED | | Live |
| K&K AIR-CONDITIONING ENGINEERING LIMITED | | Live |
| PAK LEE AIR-CONDITIONING ENGINEERING LIMITED | | Live |
| WIN YAO AIR-CONDITIONING ENGINEERING COMPANY LIMITED | | Live |
| AMBITIOUS AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| BROADMARK AIR-CONDITIONING & ENGINEERING COMPANY LIMITED | Private company limited by shares | Dissolved |
| Century Air-Conditioning Engineering Limited | Private company limited by shares | Live |
| CHUNG WAI AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| CONCORD AIR-CONDITIONING & ENGINEERING COMPANY LIMITED | Private company limited by shares | Dissolved |
| CONCORD AIR-CONDITIONING & ENGINEERING CO. LIMITED | Private company limited by shares | Live |
| eFast Air-conditioning Engineering Limited | Private company limited by shares | Live |
| WING WO ELECTRICAL ENGINEERING & AIR-CONDITIONING COMPANY LIMITED | Private company limited by shares | Dissolved |
| Everest Air-conditioning Engineering Co. Limited | Private company limited by shares | Live |
| FEDEX AIR-CONDITIONING & ENGINEERING LIMITED | Private company limited by shares | Dissolved |
| Galaxy Air-Conditioning Engineering Limited | | Live |
| GEMSTAR AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| GLOBESHINE AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| HENRY AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| HONEST AIR-CONDITIONING & ENGINEERING LIMITED | Private company limited by shares | Live |
| ICICLE AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Dissolved |
| KONG TAI AIR-CONDITIONING AND ENGINEERING CO. LIMITED | Private company limited by shares | Live |
| KIN LONG AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| MING KEE AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Dissolved |
| MING TAT AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| WAH NANG AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| KIN NGAI AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| OCEAN AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Dissolved |
| ONEWAY AIR-CONDITIONING ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| REALTY AIR-CONDITIONING AND REFRIGERATING ENGINEERING COMPANY LIMITED | Private company limited by shares | Dissolved |
| RICH BOND AIR-CONDITIONING & ENGINEERING LIMITED | Private company limited by shares | Live |
| SHAM WO AIR-CONDITIONING & ENGINEERING COMPANY LIMITED | Private company limited by shares | Dissolved |
| SHENG TAI AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| SMART AIR-CONDITIONING ENGINEERING LIMITED | | Live |
| SUNRISE AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| TELLY AIR-CONDITIONING & ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| VICTOR AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| PO YUEN AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| YUNG KEE AIR-CONDITIONING ENGINEERING CO. LIMITED | Private company limited by shares | Live |
| WING HONG AIR-CONDITIONING EQUIPMENT LIMITED | Private company limited by shares | Live |
| EURO AIRCONDITIONING LIMITED | Private company limited by shares | Dissolved |
| Flying Dragon Air-Conditioning & Engineering Company Limited | Private company limited by shares | Live |
| FORTUNE AIR-CONDITIONING ENGINEERING LIMITED | Private company limited by shares | Live |
| FUGI AIR-CONDITIONING TRADING COMPANY LIMITED | Private company limited by shares | Dissolved |
| NEW WING FUNG AIR-CONDITIONING COMPANY LIMITED | Private company limited by shares | Live |
| WING FUNG AIR-CONDITIONING LIMITED | Private company limited by shares | Live |
| GLORY AIR-CONDITIONING LIMITED | Private company limited by shares | Live |
| GOOD SYSTEM AIR-CONDITIONING & ENGINEERING LIMITED | Private company limited by shares | Live |
| GOOD WELL AIR-CONDITIONING LIMITED | Private company limited by shares | Live |
| HANG FAT AIR-CONDITIONING COMPANY LIMITED | Private company limited by shares | Dissolved |
| HANG FAI AIR-CONDITIONING & ENGINEERING LIMITED | Private company limited by shares | Live |