According to different requirements of cleanroom, fan filter units (FFU) have different components. However, no matter what kind of fan filter unit is, it still has basic parts that enable it to provide clean air for cleanroom.

I. Fan Filter Unit (FFU) Components

These basic parts include pre-filter, housing, air pipe connecting parts, motor, blower wheel, airflow equalization device, final filter, protective net, controller

II. Details Of Fan Filter Unit Components

1. Pre-filter

The main task of pre-filter is to prevent damage to HEPA filter caused by construction debris.

2. Housing

The material of housing is steel, galvanized steel, powder-coated steel, stainless steel, etc. There are varying options for different use environments. The housing thickness is about 1.2~2.0 cm.

3. Air pipe connecting parts

In cleanrooms with a low level of cleanliness, there is no static pressure on the ceiling, the air pipe connecting parts make the connection between air pipe and FFU more convenient.

4. Motor

Both AC motors and DC motors are used in fan filter unit. DC motor is big, expensive, easy to control and highly engery-consuming, while AC motor is smaller, cheaper. and more energy-saving. The control of AC motor requires the corresponding technology. The service life of motor in fan filter unit ranges from 40 000 to 100 000 hours.

Some high-quality motor has oil-free lubrication, sealed bearings, thermal overload protection, and long service life.

5. Blower wheel

There are two types of blower wheel: the forward curved centrifugal type and the backward curved centrifugal type.

The forward one provides large air volume and enhances the dust removement, while the backward one reduces the energy consumption and noise.

fan filter unit blower wheel

6. Airflow equalization device

With varying demands of FFU, many manufacturers have begun to equip FFU with the airflow equalization device to adjust the outlet airflow of FFU, thereby improving the flow distribution in clean room.

There are 3 types of equalizing devices: The first is an orifice plate, and the outlet airflow of the FFU is adjusted mainly by the dense distribution of the holes on the plate. Second is the grille, which adjusts the FFU outlet airflow mainly through the density of the grille. The other is the power curve, which mainly induces the flow of airflow through the shape of the curve, and at the same time regulates the airflow through the dense distribution of holes on the curve.

7. Final filter

Final filter is HEPA filter or ULPA filter. Read more about these filters here

8. Protective net

Its function is to protect the filter, most of which is anti-static

ffu fan filter unit protective net

9. Controller

FFU can be roughly divided into several types of switch, continuous adjustment, computer control, etc. The functions performing at the same time include single control, partition control, alarm, and operation status display.

fan filter unit control switch


Vietnam Cleanroom Equipment (VCR) specializes in providing cleanroom equipment for construction contractors. We provide high-quality products with competitive prices and large quantities nationwide. The equipment includes:

Differential pressure gauge, FFU Fan Filter Unit, Pass box, Clean room air filter, HEPA box, Clean booth, cleanroom steel door, Isolator cabinet, and other equipment

For details, please refer to Vietnam cleanroom equipment official website