Round single-channel variable air volume terminal (Optimized VAV Box) includes damper and flow sensor and can be equipped with different control equipment according to the user. These terminals adjust the required air volume of the space according to the feedback they get from the thermostat inside the room. These terminals are able to deliver hot and cold air to the space at the same time, and in the conditions that such terminals are used to control hot and cold air, a dual-function thermostat and an air temperature sensor at the entrance, as well as controls to change the system from cooling to heating, must be used. and vice versa. Usually, variable air volume terminal types are used in the interior spaces of buildings that have a constant cooling load and do not need heating.

Flow control: electronic

Differential pressure range: 20 to 1000 pascal

Leakage: Very low damper vanes in fully closed position

Operating temperature: between 10 and 50 degrees Celsius

Body: completely airtight without leakage

Due to the presence of exhaust hoods (fume hoods) and numerous air extraction units (extraction units) in laboratories and clean rooms (Clean Rooms), complex requirements are considered for air supply and exhaust. The amount of air circulation required for laboratories is 8 times during the day and 4 times during the night. In addition to the amount required for air circulation, which is stated by the standard DIN194, part 7, the balance of flow rate and maintaining pressure (negative pressure in laboratories and positive pressure in clean rooms) as well as maintaining comfort conditions such as temperature, humidity and air flow. should be considered. The high rate of air flow rate changes caused by the variable load of consumers (exhaust hoods and extraction units) should be quickly identified and the amount of supply/exhaust air required by the room should be provided quickly according to the new conditions. When choosing suitable controllers for supply air, it is necessary that the operation time of the controller does not exceed 5 seconds (for a 90 degree rotation). With operating times higher than 5 seconds, it is difficult to maintain adequate pressure in laboratories for different working conditions. In the process of planning for the whole system, maintaining proper conditions to protect personnel from dangerous substances and ensuring people’s health should be taken into consideration. It should be noted that the price of the inspection valve and air distribution terminal is determined according to the quality of the product.