Ventilation and Cooling Project for a Farmers’ Market in Fuzhou, Fujian Province

Project Overview

This project is located in Fuzhou, Fujian Province, serving a semi-open, large-span steel-structure farmers’ market. The market features fixed shops along the west side, while the other three sides have open access passages. The market faces challenges such as high heat transfer through the enclosure, high customer density, and poor natural ventilation. Due to construction dust from an adjacent site, the original ventilation openings on both sides of the market’s roof have been sealed, further weakening indoor ventilation and exacerbating heat accumulation. In summer, the maximum indoor temperature can reach 35–40 °C.

The high-temperature environment not only significantly reduces shopping comfort but also adversely affects the storage and preservation of fresh produce. There is an urgent demand from vendors, management, and consumers alike for environmental improvements. A comprehensive solution that integrates cooling, ventilation, dust control, and energy efficiency is urgently needed.

Operational Design

This project utilizes 18 Aolan “Silent King” series evaporative air coolers to provide overall ventilation and cooling for a central market area of approximately 900 m². The units are installed on the roofs of the shops on the east and west sides of the roof, arranged in a staggered, opposing configuration. The coolers are connected to air ducts that deliver air directly into the indoor space through openings near the skylights, enhancing uniform air distribution. The system adopts a slight positive pressure design, effectively preventing external construction dust from entering while ensuring a continuous supply of fresh air, greatly improving indoor comfort and cleanliness.

The units are equipped with centrifugal fans, capable of long-distance air supply and providing cooling coverage throughout the entire space without dead spots. The "Silent King" series offers significantly better noise control than conventional fan products, making it suitable for public environments such as farmers’ markets and supermarkets that require a high-quality acoustic environment, thus meeting comfort expectations.

The solution also includes a seasonal operating logic: during most of the summer, the system uses direct evaporative cooling with wet pads to meet indoor cooling demands while saving energy. In winter, the units can be turned off or operated without the cooling function, serving only as a fresh air system to improve air circulation and reduce odor accumulation.

Project Significance

The project was commissioned in 2025. After system commissioning and optimization, the equipment operates stably. Measured data show: on a typical summer day with outdoor dry-bulb/wet-bulb temperatures of 35.2 °C / 28 °C, the coolers’ discharge air temperature is approximately 29.5 °C, and the average indoor temperature is maintained at around 30 °C.

The use of evaporative air coolers has effectively regulated indoor temperature, enhanced air circulation, and completely resolved the three core pain points of high heat, odors, and dust. It has significantly improved the overall market environment for both business operations and customer experience, effectively reduced the cost of preserving fresh products for vendors, and has received unanimous recognition from both the management and vendors.