Air filter box, also known as purification filter box or fresh air filter box, has two ways of air outlet: circular and square. Air filter box is a necessary air purification equipment for food QS certification. The internal structure of the air filter box is installedPrimary air filter，Efficient air filterComposed of fans. It can also be calledBoosting fresh air cabinetThe fresh air filter box, installed at the end of the exhaust system, also known as the exhaust box, can effectively filter out harmful gases and infections generated during production or biological operations.

1、 Introduction to Air Filter Box:
The fresh air system refers to an air duct system that obtains air from outdoors, filters and humidifies it through an air filter box, and sends it into the room. The fresh air system regulates and controls the amount of fresh air in the room to meet people's normal needs, avoid air conditioning problems, and prevent air tightness caused by insufficient fresh air volume.

The air filter box is composed of a filter, a surface cooler, a heater, a humidifier, and a fan. Its structure is simple, and there is a high possibility of failure. The air filter box may be used for temporary heating during the construction phase before it is officially put into operation. It is a heat exchange equipment that is prone to freezing and cracking. When the outdoor temperature is low, any link of pressure testing, pipeline flushing, and operation is prone to freezing and cracking faults.

Insufficient attention to the safe operation of air filtration boxes often leads to the freezing and cracking of heat exchangers, which not only causes economic losses to the air conditioning system itself, but also results in significant indirect economic losses from water disasters caused by the freezing and cracking of heat exchangers. This is because heat exchanger freezing and cracking accidents are often discovered later, and the flowing water often endangers nearby elevators, cable shafts, and floors below. If the safe operation of the air filter box is taken seriously in various stages such as construction, commissioning, and operation, the freezing and cracking accidents of its heat exchanger can be basically avoided.2、 Inspection items for air filter box before and after startup:
1. Check if the drive belt of the fan is loose. If it is stretched by more than 2CM when tightened by hand, it should be replaced (optional model).

2. Check if the bearings of the fan and motor are normal, and add lubricating oil once (optional model).

3. Check if the condenser coil is clean and if there are any foreign objects at the outlet of the water tray. If there are any, clean and remove them.

4. Check if the heater is functioning properly, measure the voltage and resistance, and repair or replace it if there are any abnormalities.

5. Check for any other abnormal conditions inside the machine and whether the inner panel is sealed after installation.

6. Check the sealing and leakage of the filter.

7. Check if the inlet and outlet air valves are in the open position.3、 Daily inspection and maintenance of air filter box:
The filter inside the air filter box should be cleaned once a month.
1. Before cleaning the air filter box, gently tap one end of the hand-held filter bag with a wooden stick to remove the dust and other substances adsorbed on the filter bag and soak it in water to wash away the floating dust.

2. Soak and clean the air filter box with laundry detergent or cleaning agent.

3. Wash the filter box with drinking water to remove the cleaning solution, and then dry it in the sun or oven.

2. Pay attention to the working current of the daily air filter box

3. The air filter box must pay attention to the pressure difference before and after the air filter. If the pressure difference is too large, it should be cleaned in time.

4. Pay attention to the wear of the filter box belt, and replace it promptly if the belt is severely worn.

4、 Suggestions for safe operation of air filter box
1. Pay attention to the anti freezing of all air conditioning equipment and pipelines during winter operation. During pipeline pressure testing and flushing, attention should be paid to the outdoor temperature, and the system must be completely emptied after flushing. Temporary heating with an air filter box should also be tested for water according to normal procedures. If there are no self-control measures and dedicated management, it is recommended not to use fresh air conditioning equipment for temporary heating.

2. Establish and improve operational management systems. The air filter box that is not used at night should also use a fixed water flow rate or a temperature controller to automatically control the opening of the water valve or install an electric heating device to ensure the temperature of the air filter box heater. During winter operation, the air filter box should be regularly inspected to track weather changes. It is not advisable to arrange debugging and maintenance of the air conditioning system in cold weather to ensure the safety of the air conditioning water system operation.

3. Effective anti freezing automatic interlocking monitoring devices must be installed in the design of air filtration boxes. When the fan is running, the rated water flow rate of the heater must be ensured first. When the water temperature is too low or the water flow rate is too low, there should be an alarm function and the supply fan and fresh air inlet insulation air valve should be closed in a timely manner.

5、 Common faults of air filter box:
1、 Reason for air filter box not supplying air:
1. The fan is not rotating; Confirm the method and go to the fan section to check if the fan is running. Solution: Check if the motor of the air filter box is powered, if the external power supply is powered, and if the motor is damaged.

2. The air supply valve of the air filter box is not open. Go to the air supply section to check if the air valve is open. The handling method is to immediately stop the machine and check whether the control action of the air supply valve is normal, and whether the mechanical port connecting rod of the air supply valve is normal.2、 Reason for excessive air supply volume in the air filter box:
1. The static pressure of the fan is less than the set value; Confirm the method, measure the static pressure of the fan, and compare it with the design value. Processing method, check whether the air duct balance has been completed, check whether the filter screen is installed, and check whether the external air outlet louvers are installed.

2. The fan speed is too fast; Confirm the method, adjust the speed, and check if it will reduce the indoor pressure. Handling method, reducing speed, checking fan speed and control facilities.

3、 Reasons for the low air supply volume of the air filter box:
1. The static pressure of the fan exceeds the original set value; Confirm the method, measure the static pressure of the fan, and compare it with the design value. Handling method: Check if there are any air valves that are not open in the air duct, check if the filter screen is dirty or blocked, and check the balance of the air duct.

2. The fan speed is too slow; Confirm the method, increase the fan speed, and monitor whether there is improvement. Processing method, increase the fan speed, and check whether the fan speed and control set value are correct.
3. Fan reversal; Confirm the method and check if the fan direction is normal. Processing method and correction of wiring.

4. The opening of the pressure relief valve causes a short circuit; Road confirmation method, check if the pressure relief valve is open. Solution: Close the pressure relief valve.4、 Reasons for excessive vibration of the air filter box body:
1. Poor suspension of the fan, measure vibration and make corrections.

2. Poor installation, inspection, and correction of the fan.

3. The fan supply air volume is too high. Measure the fan air volume and refer to fault 2.

4. The connection between the fan and the motor is damaged. Please inspect and correct it.

5. The overall structure of the fan resonates at a certain speed. Using this speed as the reference point, adjust the speed to increase or decrease and inspect the overall vibration condition. Find the resonance source and correct it.
6. Is the static pressure of the fan too high, deviating from the normal operation of the fan, causing vibration of the fan. Measure the air volume and static pressure and inspect the fan on the performance curve of the windmill. Review whether the current operation of the windmill is reasonable and make corrections.

attachThe specifications and dimensions of the air filter box are made according to customer requirements!