Air filtration in ventilation systems
Filters in air handling catch particles from the supplied or circulating air. The type of insert is chosen according to the required purity, flow rate and design of the filter unit.
From air supply to particle capture
The air passes through the medium on which the particles are captured. As they accumulate, the resistance of the filter increases; this changes the pressure drop and can decrease the flow rate or increase the energy consumption of the fan. Therefore, monitor the condition of the insert according to the operating values and instructions of the unit manufacturer.
Panel and pocket design
Panel filter offers a compact surface; a pocket filter uses more media in the unit space. The choice depends on frame size, available depth, flow rate and desired efficiency. The number and length of pockets and their distribution must correspond to the construction. The insert is supposed to seal in the frame - the air bypass around the media reduces the efficiency of the entire filter section.
What to consider when choosing
Basic inputs for selection:
- dimensions and method of installation in the filter unit
- the amount and nature of particles in the air
- required flow rate and required filtration efficiency
- temperature, humidity and other environmental influences
- operating pressure drop and replacement options
Operation and replacement
Inspection is to detect fouling, damage and leakage before they affect the system. Do not plan the replacement just according to the calendar: follow the manufacturer's recommendations and actual operation, especially the development of the pressure loss.
Airfilter pockets and cartridges are listed amongfilter elements.