Gravity Louver Automatic Exhaust Device with High-Strength Aluminum Alloy Non-Return Function and Custom Sizes

Product Introduction

The Gravity Louver (Gravity Grille) is a non-return automatic exhaust device specifically designed for positive pressure commercial building HVAC systems. Manufactured from high-strength aluminum profiles, it operates using the natural downward force of gravity — blades open to exhaust air when indoor pressure exceeds outdoor pressure, and automatically close to prevent backdraft when pressure equalizes. This product is widely used for automatic exhaust in office buildings, shopping malls, hotels, hospitals, and other commercial spaces with positive pressure air conditioning systems.

Applicable Locations

With its purely mechanical gravity operation, requiring no power supply and minimal maintenance, the Gravity Louver is widely used for commercial building automatic exhaust applications. Typical applications include:

Product Advantages

1. Gravity Closure – Non-Return Backdraft Prevention

Blades naturally hang downward by gravity. When indoor pressure exceeds outdoor pressure, airflow pushes blades open for exhaust. When exhaust stops or indoor pressure drops, blades automatically close. This design effectively isolates indoor-outdoor air exchange and prevents reverse airflow — providing reliable non-return function.

2. No Power Required – Energy-Saving and Maintenance-Free

Pure mechanical design — no external power or electrical control needed. Operates automatically based on pressure difference and gravity. Zero energy consumption, zero noise, zero maintenance — more energy-efficient than motorized dampers. Ideal for standard pressure exhaust applications without signal control requirements.

3. Aluminum Alloy – Lightweight and Durable

Manufactured from high-strength aluminum alloy — lightweight, high strength, resistant to deformation and corrosion. Available with anodized, powder coating, or baking paint finish — suitable for both indoor and outdoor applications.

4. Sturdy Construction – Good Sealing

Blades and frame fit tightly together. When closed, effectively isolates airflow. Optional sealing gaskets available for enhanced airtightness. Blades are parallel to the ground — rectangular louvers typically have blades parallel to the short side for a clean, organized appearance.

5. Custom Sizes – Adaptable to Various Duct Requirements

Available in square, rectangular, and circular configurations. All sizes can be customized to suit exhaust ducts, ventilation shafts, fresh air intakes, and other project requirements. Custom colors available including natural, white, and RAL standard colors.

Technical Specifications

Installation & Maintenance Instructions

Application & Selection Recommendations

About Us:
  Guangzhou Xingjin Fire Equipment Co., Ltd. is a professional enterprise dedicated to the research, development and production of HFC-227ea (FM200), Novec1230, CO2 and inert gas products. For many years, the company has been committed to improving product quality, enriching product varieties and optimizing product specifications.
  At present, our company's popular FM200 products are widely used, such as: pipe network FM200 fire extinguishing system, cabinet FM200 fire extinguishing system, automatic FM200 fire extinguisher (ceiling type), fire detection tube fire extinguishing system, and automatic fire extinguishing pipe. In addition, our inert gas fire extinguishing systems are also becoming increasingly popular, such as the IG541 (nitrogen) fire extinguishing system, IG100 (nitrogen) fire extinguishing system, and IG55 (argon) fire extinguishing system. Due to our high-quality products and services as well as our good reputation, our company is highly praised by customers all over the world.

Our factory:
  The factory is divided into multiple areas, mainly used for the production of gas cylinders, gas filling, product inspection, goods packaging, storage of goods, sample display, etc. We have our own professional production and testing equipment, such as bottle washing machines, dryers, valve loaders, gas filling machines, etc

Our products:
  HFC-227ea (FM200), Novec1230, CO2 and inert gas series products (such as pipe network, suspended, external pressure storage, cabinet, integrated cabinet, fire detection pipe, portable fire extinguisher, gas cylinder), fire extinguishing pipe, complete alarm system, foam fire extinguishing series (such as vertical/horizontal foam tank, foam agent, filling machine, fire cannon), hot aerosol and other fire extinguishing equipment .

Our services:
   We have a professional and mature team, including a solution design team, a skilled installation team, a quality inspection team and an after-sales service team.
 

Our honors:
   Since its establishment in 2010, the company has won numerous praises and honors. In 2014, it was awarded the title of "AA-level Credit Company" by the China Fire Protection Association. In addition, all of our products have passed the CCC test and have relevant certificates for each product.
 

The main market:
  Our target customers are people all over the world who need fire-fighting equipment. So far, we have rapidly developed the market in Southeast Asia, the Middle East and Africa, and have received high praise from a wide range of customers. In the coming years, we will strive to explore other foreign markets.

We are ready for challenges, so please do not hesitate to send an inquiry to us!