Industry code 4322 Installation of water supply, drainage, heating, and air conditioning systems, most recently updated according to Decision 36/2025/QD-TTg. To learn more about the details of industry code 4322, please refer to this article by VN Law Firm!
1. What is a business industry code?
Business industry code is a series of numbers coded to represent a specific business industry. Organizations and individuals, when preparing business registration documents, must use this business industry code table for registration. The 4-digit industry code (level 4) is the code used for business registration.
The Vietnam Standard Industrial Classification (VSIC) system, issued under Decision 36/2025/QD-TTg, has a hierarchical structure with 5 levels, from general to detailed:
| Level | Name | Code | Quantity |
|---|---|---|---|
| Level 1 | Industry Level 1 | 1 letter (from A to V) | 22 industries |
| Level 2 | Industry Level 2 | 2 digits (according to Level 1) | 87 industries |
| Level 3 | Industry Level 3 | 3 digits (according to Level 2) | 259 industries |
| Level 4 | Industry Level 4 | 4 digits (according to Level 3) | 495 industries |
| Level 5 | Industry Level 5 | 5 digits (according to Level 4) | 743 industries |
Example of industry code structure: Taking the food manufacturing industry as an example:
- Level 1: C (Manufacturing)
- Level 2: 10 (Food processing and manufacturing)
- Level 3: 107 (Manufacture of other food products)
- Level 4: 1075 (Manufacture of prepared meals and dishes)
- Level 5: 10751 (Manufacture of prepared meals and dishes from meat)
2. Regulations on Industry Code 4322 Installation of water supply, drainage, heating, and air conditioning systems
| Industry Code | Industry Name |
|---|---|
| 4322 | Installation of water supply, drainage, heating, and air conditioning systems |
| 43221 | Installation of water supply and drainage systems |
| 43222 | Installation of heating and air conditioning systems |
This group includes: Installation, repair, and maintenance of plumbing, heating, and air conditioning systems in buildings or other construction projects, including extensions and alterations, specifically:
– Installation, repair, and maintenance of:
+ Heating systems (electric, gas, oil), such as heat pumps, solar collectors,
+ Furnaces, cooling towers,
+ Water supply, drainage, and sanitary equipment,
+ Ventilation, refrigeration, or air conditioning equipment,
+ Gas appliances,
+ Steam pipes,
+ Fire sprinkler systems,
+ Irrigation sprinkler systems,
– Construction or installation of brick fireplaces;
– Installation of ductwork.
This group also includes: Installation, repair, and maintenance of medical gas distribution systems in hospitals.
Excludes:
– Installation of electric heating systems is classified under group 43210 (Installation of electrical systems);
– Camera inspection of air ducts, water and gas pipes, and other liquids without repair or installation is classified under group 71200 (Technical testing and analysis).
43221: Installation of water supply and drainage systems
This group includes:
Installation, repair, and maintenance of water supply and drainage piping systems in buildings or other construction projects, including extensions and alterations.
Specifically:
– Water supply, drainage, and sanitary equipment;
– Steam pipes;
– Fire sprinkler systems;
– Irrigation sprinkler systems;
– Installation of water supply and drainage piping systems.
43222: Installation of heating and air conditioning systems
This group includes:
Installation, repair, and maintenance of heating and air conditioning systems in buildings or other construction projects, including extensions and alterations.
Specifically:
– Heating systems (electric, gas, oil), such as heat pumps, solar collectors;
– Furnaces, cooling towers;
– Ventilation, refrigeration, or air conditioning equipment;
– Gas appliances;
– Construction or installation of brick fireplaces;
– Installation of air conditioning ductwork.

3. Suggested ways to record Industry Code 4322 Installation of water supply, drainage, heating, and air conditioning systems
– When registering to establish an enterprise, when notifying changes to business lines, or when requesting a change to a Business Registration Certificate, the enterprise founder or enterprise selects a four-level economic sector in the Vietnam Standard Industrial Classification System to record the business lines in the enterprise registration dossier. The business registration agency guides, cross-references, and records the enterprise’s business lines in the National Business Registration Database.
– For conditional business lines stipulated in other legal documents, the business lines are recorded according to the regulations in those legal documents.
Suggested ways to record Industry Code 4322 Installation of water supply, drainage, heating, and air conditioning systems:
Case 1: General
| Industry Code | Industry Name |
|---|---|
| 4322 | Installation of water supply, drainage, heating, and air conditioning systems |
Case 2: Detailed
| Industry Code | Industry Name |
|---|---|
| 4322 | Installation of water supply, drainage, heating, and air conditioning systems (excluding electroplating; mechanical processing) |
Case 3: Detailed
| Industry Code | Industry Name |
|---|---|
| 4322 | Installation of water supply, drainage, heating, and air conditioning systems (excluding mechanical processing, waste recycling, electroplating at the head office, and excluding the installation of refrigeration equipment (freezing equipment, cold storage, ice machines, air conditioners, water chillers) using R22 refrigerant in the field of seafood processing) |
Case 4: Detailed
| Industry Code | Industry Name |
|---|---|
| 4322 | Installation of water supply, drainage, heating, and air conditioning systems (excluding the installation of refrigeration equipment (freezing equipment, cold storage, ice machines, air conditioners, water chillers) using R22 refrigerant in the field of seafood processing and excluding mechanical processing, waste recycling, electroplating at the head office) |
Case 5: Detailed
| Industry Code | Industry Name |
|---|---|
| 4322 | Installation of water supply, drainage, heating, and air conditioning systems Details: Installation of piping systems, heating, and air conditioning in buildings or construction works, non-electric solar collectors, ventilation, refrigeration, or air conditioning equipment; Installation of ductwork (excluding mechanical processing, waste recycling, electroplating at the head office) (excluding the installation of refrigeration equipment (freezing equipment, cold storage, ice machines, air conditioners, water chillers) using R22 refrigerant in the field of seafood processing) |
Note: Depending on the specific industry code and business line, as well as specific regulations in each locality, it may be necessary to provide detailed descriptions for the 4-digit industry code or commit to operating according to regulations.
4. Services for changing business lines for companies and enterprises at VN Law Firm
Business line change services for companies and enterprises at VN Law Firm help customers save a significant amount of time and effort. Coming to VN Law Firm, you will be provided with business line change services for companies and enterprises, including:
- Consulting on the process and procedures for changing or supplementing business lines;
- Advising clients on preparing necessary documents;
- Drafting and submitting the dossier for changing or supplementing the company’s or enterprise’s business lines on behalf of the client at the Business Registration Office;
- Monitoring the dossier, supplementing or correcting the dossier (if any) as required by the specialist;
- Performing the procedure to publicize business registration information on the Information Portal;
- Handing over the confirmation of business line change;
- Guiding clients on procedures to note after changing business lines…
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