With many years of experience in the field of consulting, design and construction of HVAC systems according to ventilation standards in the world and in Vietnam. P69.JSC ensures to bring a green, clean space for users and saves energy.

The air-conditioned environment is a closed space, so there is no natural air exchange, so if you want to provide O2, it is necessary to provide a certain amount of air in accordance with human needs.

A ventilation system is a system that helps to change or replace the amount of air inside a fixed space to provide a source of high-quality air for the living environment in that space. The ventilation system installed will help control the temperature, add oxygen or remove odors, moisture, harmful bacteria as well as CO2. When the air source is circulated through this system, the outside air will be brought in, and at the same time, the exhaust gas from the inside will also be pushed out, forming a continuous circulation cycle, helping to prevent air pollution. prevent stagnation of the air.

Typical construction ventilation systems of P69.JSC:

  • Factory ventilation system.
  • Office ventilation system.
  • Ventilation system basement, garage.
  • The ventilation system pressurizes the stairs.

When installing ventilation systems, we need to comply with the following regulations:

  • All dimensions must be checked on site prior to duct production.
  • All ductwork installation must be carried out by a specialist approved for duct manufacture and installation. Ducts should not come into direct contact with the building structure or building finishes but must be isolated by means of an isolating pad.
  • Manufacturing shall be carried out in a compact and finished manner with all ducts of the correct size dimensions and cross-sections, braced and stiffened as specified and all internal and external surfaces not protruding and have sharp edges.

During the installation of the ventilation system, at each main branch in the duct, and the inlet and outlet of each fan, arrange a sufficient number of test holes to balance the system. Also, arrange test holes for fan ejectors and at all equipment. Inspection holes shall be located within easy reach of the working platform or ladder. Each inspection hole shall be of the appropriate size for the equipment used and shall be closed with a ribbed rubber stopper to ensure airtightness. The connection between ductwork sections must comply with installation details.

  • Reinforcement holes must be arranged at the place where thermometers, manometers, sensors, gauges, damper bars, etc. are installed in the pipeline. Expansion rings shall be provided for reinforcement holes where they are located in the insulated ductwork.
  • In places where copper pipes go through ducts or equipment casings, rubber washers must be arranged to avoid damage to copper pipes.
  • Ducts must be suspended or firmly supported from the building structure. Expansion bolts are used. Splints activated by particles generated by explosives are not acceptable.
  • Angle trapezoidal hangers with supports up to 2m apart must use “C” beams, clamps will not be accepted. Provide necessary angle steel as required to brace ducts or equipment and to support ducts from the building structure.
  • A layer of 5mm burlap of compressed thickness shall be provided between any supporting members which are designed to clamp or hold the pipe (e.g., round pipe strip clamps) or the member on which the pipe rests. All brackets are not hot-dip galvanized.
  • Pipe size increase must be increased gradually. When the maximum width or dimension of the conduit is over 450mm, the pipes shall be reinforced by bending at a break-through corner in either direction.
  • Ducts must be self-supporting. Single thickness bulkheads between pipes are not accepted. The interior parts that are visible through the vents will be painted matte black.
  • All tolerances must be made during the “installation of pipes” to frame the structure of the building, and where changes or offsets are required, sections must be maintained.
  • However, all these changes must be approved and installed according to the instructions at the time.
  • During installation, the open ends of pipes should be protected by sealing, corrugated iron screens are fastened to prevent debris and dirt from entering.

  • When pipes are shown connecting to openings along the edges of floors, walls, etc. Provide 30 X 30 X 4 mm galvanized angle steel that is bolted to the structure and must be gas sealed with compounds. putty in the corners. Sheet metal at these locations shall be bolted to the angle steel frame.
  • All ducts, housings, air boxes, etc. must be made of high-quality galvanized corrugated iron sheets without air bubbles, stains, imperfectly coated spots, etc. Sheet metal is not allowed. low quality.
  • If damage occurs on galvanized ductwork, it must be replaced with another piece at no additional cost to the contract.
  • Pipes shall be constructed with double welds or Pittsburgh lock welds. All welds shall be hammer hammered and air-tight by applying sealants prior to hammering. For horizontal couplings, refer to applicable SMACNA or  ASHRAE  guidelines for low-pressure conduit.
  • Clamp-lock couplings are not accepted.
  • Support vertical ducts mounted in different axes at the floor with galvanized steel brackets of approved sizes. Install these angle steels along the width of the shaft with their ends attached to the angle steel firmly anchored to the shaft masonry walls or to the frame of floor openings. Ducts shall be attached to these supports with bolts.
  • Ensure that all necessary openings through floors, walls, partitions, etc. for ventilation are arranged in the correct positions as required.
  • Each ductwork shall be cleaned internally and externally prior to installation and all open ends shall be covered and sealed to prevent contamination during construction.
  • Make sure that the ductwork is clean and free of dirt, debris, etc. before operating the fan for the first time. Do not operate the fan until the filters are installed and approved by the consultant.
  • The bottom joint and 150mm of the fresh air vertical joint and the mixing box shall be made watertight with a suitable sealant. Connect the drain and take the copper drain hose to the nearest floor drain.
  • All fixings including nuts, bolts and washers, etc. are used in the construction and installation of the ventilation system. Galvanized duct supports shall be galvanized or cadmium plated.
  • The connection to the air outlet must use a flexible duct. Flexible ducts have a maximum length of 4m and must be insulated if the ducts are in the air conditioning system.

Contact us today for a free consultation and answer at:


Headquarter: No. 6/165C Xuan Thuy, Cau Giay District, Hanoi

Hotline: 02422121212 – 09656937799



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