In HVAC systems, fiberglass ducts are widely used in commercial buildings, public buildings, and industrial plants due to their integrated insulation, sound absorption, and ductwork functions. Compared to traditional sheet metal ducts with insulation, fiberglass ducts offer advantages such as lightweight structure and high installation efficiency. However, inadequate process control during actual construction can easily affect system performance. This article explains common problems in fiberglass duct construction for project reference.

Firstly, there is the issue of improper material selection. Fiberglass ducts have specific requirements for sheet density, thickness, and surface coating. Using sheets with low density or insufficient strength can easily lead to deformation during operation, affecting airflow and system stability. Furthermore, if the inner and outer lining materials do not meet design requirements, it may create problems related to moisture resistance, cleanliness, or durability. Before construction, product technical parameters and relevant test reports should be strictly verified to ensure that materials meet engineering standards.

The second common problem is insufficient processing precision. Fiberglass ducts are often cut, grooved, and spliced on-site or in prefabrication workshops. Inaccurate processing dimensions can lead to loose joints and increased air leakage. Especially at irregularly shaped parts such as elbows and tees, improper layout can easily lead to increased local resistance. The proper practice is to accurately cut materials according to the design drawings and use specialized tools for bending and assembly.

Thirdly, inadequate joint and sealing treatment is a problem. The system performance of fiberglass ducts largely depends on the quality of the joints. Uneven adhesive application, weak sealing tape, or insufficient compaction of joints can easily lead to air leaks and detachment. During construction, the amount of adhesive used and curing time should be strictly controlled, and key areas should be thoroughly inspected to ensure overall sealing.

Fourthly, improper support and hanger placement is a problem. Due to the lightweight nature of fiberglass ducts, some projects neglect the spacing and stress distribution of supports and hangers, resulting in localized duct sagging or concentrated stress at joints. Support and hanger spacing should meet relevant specifications and be rationally arranged according to the duct cross-sectional dimensions to avoid deformation after long-term operation.

Fifthly, insufficient moisture protection and finished product protection are also issues. Fiberglass ducts are highly sensitive to the construction environment. In high-humidity or unsealed construction sites, without effective protective measures, the ductwork is prone to moisture absorption, affecting its strength and lifespan. After installation, the duct openings should be sealed promptly to prevent dust and debris from entering and ensure system cleanliness.

Finally, the system acceptance process is often neglected. Some projects fail to conduct a comprehensive inspection of air leakage rate, appearance quality, and system operation after installation, potentially leaving hidden problems. A standardized acceptance process helps identify and rectify issues promptly, and is crucial for ensuring the long-term stable operation of fiberglass ducts.

Overall, the construction quality of fiberglass ducts is closely related to material selection, processing technology, and on-site management. Only by standardizing construction procedures, strengthening quality control, and paying attention to detail can the comprehensive advantages of fiberglass ducts in HVAC systems be fully realized, providing buildings with stable, efficient air delivery and energy-saving effects.