| SKY AIR-CON LIMITED | Private company limited by shares | Live |
| BEN & CO. AIR-COND. LIMITED | Private company limited by shares | Live |
| ON KEE Air-cond Limited | | Live |
| HARBOUR AIR-COND. & ELECT. ENG CO. LIMITED | Private company limited by shares | Live |
| AUDEN AIR-COND. & ELECTRICAL COMPANY LIMITED | Private company limited by shares | Live |
| KAI HANG AIR-COND. ENG. CO. LIMITED | Private company limited by shares | Live |
| HIMCHING APPLIANCES (AIR-COND.) LIMITED | Private company limited by shares | Dissolved |
| FU KEUNG AIR-COND LIMITED | Private company limited by shares | Live |
| MING FAI AIR-COND LIMITED | Private company limited by shares | Live |
| WING FAI AIR-COND. SYSTEMS LIMITED | Private company limited by shares | Dissolved |
| LAM LAP AIR-CONDITION COMPANY LIMITED | Private company limited by shares | Dissolved |
| EMICON AIR-CONDITION (CHINA) LIMITED | Private company limited by shares | Dissolved |
| Wing Fat Motor Electric Air-condition Limited | | Live |
| WAI TAT AIR-CONDITIONAL ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| CHINA AIR-CONDITIONER MARKET ASSOCIATION CO., LIMITED | Private company limited by shares | Dissolved |
| HOP FUNG AIR-CONDITIONER WATER & ELECTRIC WORKS CO., LIMITED | Private company limited by shares | Live |
| P&W AIR-CONDITIONER & ELECTRICITY ENGINEERING COMPANY LIMITED | Private company limited by shares | Dissolved |
| ON WAI AIR-CONDITIONER ENGINEERING LIMITED | Private company limited by shares | Dissolved |
| LEE MAN AIR-CONDITIONER ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| Tin Po Air-conditioner Engineering Company Limited | Private company limited by shares | Live |
| KAM HO AIR-CONDITIONER ENGINEERING LIMITED | Private company limited by shares | Live |
| LC Air-Conditioner & Engineering Limited | Private company limited by shares | Live |
| LQ Air-Conditioner Engineering Limited | | Live |
| CHEUK KIN AIR-CONDITIONER & ENGINEERING LIMITED | Private company limited by shares | Live |
| Coolest Air-Conditioner Engineering Company Limited -The- | Private company limited by shares | Live |
| HO WAH AIR-CONDITIONER & ELECTRIC ENGINEERING LIMITED | Private company limited by shares | Live |
| EVER PROSPEROUS AIR-CONDITIONER ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| Good Day Air-Conditioner Engineering Company Limited | Private company limited by shares | Live |
| HANG TAI AIR-CONDITIONER ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| HAPPY AIR-CONDITIONER ENGINEERING LIMITED | | Live |
| LIKFAT AIR-CONDITIONER & ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| Pak Ning Air-Conditioner & Engineering Company Limited | | Live |
| TAI PING AIR-CONDITIONER ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| ProClimate Air-Conditioner Engineering Limited | Private company limited by shares | Live |
| Ruah Air-Conditioner & Engineering Company Limited | Private company limited by shares | Live |
| TELFOO AIR-CONDITIONER ENGINEERING AND TRADING COMPANY LIMITED | Private company limited by shares | Live |
| WING LEE AIR-CONDITIONER ENGINEERING LIMITED | Private company limited by shares | Live |
| TIN YING AIR-CONDITIONER ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| Choco Air-conditioner & Environment Sanitization Services Co. Limited | | Live |
| JIN FENG AIR-CONDITIONER EQUIPMENT LIMITED | Private company limited by shares | Live |
| Forever Rich Air-Conditioner & Engineering Limited | | Live |
| KAR FUNG AIR-CONDITIONER ENGINEERING COMPANY LIMITED | Private company limited by shares | Live |
| KAR FUNG AIR-CONDITIONER (HK) LIMITED | Private company limited by shares | Live |
| LI HONG AIR-CONDITIONER ENGINEERING LIMITED | | Live |
| HongFai Air-Conditioner LIMITED | | Live |
| Kwong Lee Air-conditioner Engineering Limited | Private company limited by shares | Live |
| Nickan Air-conditioner Engineering Company Limited | Private company limited by shares | Live |
| PERFORMANCE AIR-CONDITIONER ENGINEERING & TRADING COMPANY LIMITED | Private company limited by shares | Dissolved |
| PROFESSIONAL AIR-CONDITIONER & ELECTRICAL ENGINEERING LIMITED | Private company limited by shares | Dissolved |
| PROFESSIONAL ART AIR-CONDITIONER WATER ELECTRICITY ENGINEERING LIMITED | Private company limited by shares | Dissolved |
| WAI SHING AIR-CONDITIONER ENGINEERING CO., LIMITED | Private company limited by shares | Live |
| YAU SHING AIR-CONDITIONER & ENGINEERING LIMITED | Private company limited by shares | Dissolved |
| SUNS AIR-CONDITIONER & REFRIGERATION ENGINEERING LIMITED | Private company limited by shares | Live |
| HAYWA AIR-CONDITIONER SUPPLIES LIMITED | Private company limited by shares | Dissolved |
| Supreme Air-Conditioner & Engineering Company Limited | Private company limited by shares | Live |
| PAK LOK AIR-CONDITIONING COMPANY LIMITED | Private company limited by shares | Dissolved |
| SMC AIR-CONDITIONING COMPANY LIMITED | Private company limited by shares | Dissolved |
| WO LEE AIR-CONDITIONING COMPANY LIMITED | Private company limited by shares | Live |
| TAC Air-Conditioning Company Limited | Private company limited by shares | Dissolved |
| J&P AIR-CONDITIONING LIMITED | Private company limited by shares | Live |
| TAI LEE AIR-CONDITIONING LIMITED | Private company limited by shares | Live |
| AI Air-conditioning Limited | | Live |
| 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 |