What is the relationship between EFU and HEPA? Why does the EFU need a HEPA filter?
After understanding EFU, many customers will also encounter a problem:
What is the relationship between EFU and HEPA?
In fact, EFU and HEPA belong to two different concepts.
EFU is a device.
HEPA is a filter.
EFU drives the air flow through motors and fans, then uses filters such as HEPA or ULPA to filter the air, and finally sends the treated air into the interior of the equipment or a designated area.
Therefore it can be simply understood as:
EFU is responsible for 'air supply', and HEPA is responsible for 'filtration'.
3. EFU and HEPA are not the same product
This is what needs to be clarified first.
EFU’s English is:
Equipment Fan Filter Unit
In Chinese it is usually called:
Equipment side fan filter unit
It is a complete set of air treatment equipment.
And HEPA is:
High Efficiency Particulate Air Filter
Right now:
High efficiency air filter.
So the relationship between the two can be expressed as:
EFU │ ├── Motor ├── Fan ├── Box ├── Control system └── HEPA / ULPA filter
HEPA is only an important component of EFU.
4. Why does EFU need a filter?
The role of the EFU is not simply to blow air into the device.
If it is just a fan supplying air, the air entering the equipment may still contain a certain amount of particulate matter.
For some equipment with higher cleanliness requirements, these particles may affect the air environment inside the equipment.
Therefore, the air needs to be filtered before it enters the target area.
The basic process is:
Air → Fan → Filter → Clean Air → Inside the Equipment
This is why the EFU is called 'fan filter unit'.
5. What role does the HEPA filter play in the EFU?
HEPA filters are mainly used to filter particulate matter in the air.
As the air passes through the filter, some of the particles in the air are trapped by the filter media.
The filtered air then enters the inside of the device.
Therefore, the core role of HEPA in EFU can be summarized as:
Perform high-efficiency particulate filtering on the air sent into the equipment.
Specific filtration efficiency needs to be determined based on filter standards, test methods and product specifications.
6. Does EFU have to use HEPA?
uncertain.
What filter the EFU uses needs to be determined based on actual usage requirements.
For example:
General cleaning requirements
High cleanliness requirements
Specific process requirements
Equipment internal space
Air volume requirements
Wind pressure requirements
Different projects may use different filtering schemes.
Common high-efficiency filtration solutions include:
HEPA
as well as:
ULPA
Therefore, when designing an EFU, it is necessary to first clarify the cleanliness requirements of the equipment and then determine the filter type.
7. What is the difference between HEPA and ULPA?
Simply put, both are high-efficiency filters, but their application requirements and filtration performance range are different.
HEPA is usually used for air filtration with higher cleanliness requirements.
ULPA is typically used in applications with higher requirements for particulate matter control.
The specific selection needs to be based on:
Cleanliness level, target particle size, filtration efficiency, air volume, filter resistance and actual process requirements
Make judgments.
Therefore, we cannot simply think:
ULPA must be suitable for all EFUs.
The filter needs to match the entire EFU system.
8. Why does the filter affect the EFU air volume?
This is a very important point in EFU design.
Filters are not completely resistance-free.
When air passes through the filter media, it will generate a certain amount of resistance.
therefore:
The filter resistance increases → the fan needs to provide higher pressure → the EFU operating point changes
If you only replace the filter without reconsidering the fan and motor parameters, the actual air volume may be affected.
So EFU design needs to consider:
Fan + motor + filter
match between.
9. The more efficient the filter, the better the EFU performance will be?
It cannot be understood simply this way.
Filter selection needs to be based on actual needs.
For example, if the equipment only requires a certain level of cleanliness but a filter with a higher resistance is selected, more fan capacity may be needed to maintain the target air volume.
Therefore, filter selection needs to consider both:
Cleanliness requirements
Filtration efficiency
Air volume
wind pressure
Energy consumption
Installation dimensions
Usage environment
Ultimately, it is necessary to find a filtration solution suitable for the actual working conditions of the equipment.
10. Why is EFU filter size important?
For clean room FFU, the installation space is usually relatively clear.
But the EFU is usually installed inside the device.
Space inside the device may be very limited.
Therefore, the filter size will directly affect the overall structure of the EFU.
Especially for ultra-thin EFU, you need to consider both:
filter thickness
Motor size
Fan structure
air flow channel
Cabinet height
This is why the structural design of the equipment-side EFU needs to be comprehensively considered, rather than simply replacing a thinner filter.
11. How does ultra-thin EFU solve the conflict between filter and equipment space?
When the internal space of the equipment is limited, it usually needs to be coordinated in several aspects:
limited installation height ↓ filter size ↓ fan size ↓ motor layout ↓ internal air flow channel ↓ overall height of EFU
If the size of one component changes, it may affect other components.
The height of some EFU products of Aili Industrial can reach about 70mm.。
This product is mainly aimed at applications where the internal installation space of some equipment is limited.
The actual product height still needs to be determined based on air volume, filter, fan, motor and structural requirements.
12. Why can Aili Industries produce its own EFU filters?
EFU is not a separate cabinet product.
Its core components include:
Motor
fan
filter
Sheet metal structure
control system
Whole machine assembly
Aili Industrial's production system covers these key links, including filter production.
This means that in an EFU project, both:
Filter parameters → Fan parameters → Motor parameters → Box structure
Rather than treating the filter as an independent purchase part and matching it with other parts.
13. How does Aili Industrial match EFU filters?
In actual EFU projects, it can be determined according to customer needs:
filter type
HEPA/ULPA
filter size
Determine based on the EFU installation space.
Filtering requirements
Determine according to equipment cleanliness requirements.
Air volume requirements
Determine based on the actual air supply demand of the equipment.
Wind pressure requirements
Determined by combining filter resistance and system resistance.
overall structure
Determine based on filter size, motor, fan and equipment installation space.
This allows the filter to match the overall EFU structure.
14. Which industries are more concerned about EFU filters?
semiconductor
Focus on:
Cleanliness, particle control, air velocity and airflow uniformity
photovoltaic
Focus on:
Cleanliness requirements, air volume, wind speed and internal air environment of the equipment
Lithium battery
Focus on:
Cleanliness, air volume, wind speed and process environment
Panel display
Focus on:
Cleanliness, particle control, airflow distribution
Electronic manufacturing
Focus on:
Particulate Matter Control and Local Clean Environment
Precision equipment
Focus on:
Filtration performance, wind speed, noise, vibration and installation space
15. How to choose EFU filter?
You can judge in the following order:
Step One: Determine Cleaning Requirements
Identify what clean air conditions the equipment needs to achieve.
Step Two: Determine Filter Type
Choose according to actual needs:
HEPA
or:
ULPA
Step Three: Determine Filter Size
Confirm the allowed installation dimensions inside the device.
Step 4: Determine the air volume
Determine the target air volume according to the equipment process requirements.
Step 5: Determine wind pressure
Select a fan based on filter resistance and system resistance.
Step 6: Match the motor and control system
Determine the motor and control scheme based on the operating mode.
16. EFU does not determine performance solely by the filter
The operating status of an EFU is the result of the interaction of multiple components.
It can be expressed simply as:
Motor
↓
fan
↓
aerodynamics
↓
filter
↓
clean air
↓
Inside the device
Therefore, both the power system and the filtration system need to be considered when designing the EFU.
This is also the difference between device-side EFU and using filters alone.
17. Aili Industrial EFU products
Aili Industrial produces EFU, FFU and other purification equipment, and its production system covers:
Motors, fans, automatic control system software and hardware, sheet metal, filters and complete machine assembly.
For EFU products, depending on the device:
Installation space, air volume, wind speed, filtration requirements and control methods
Configure the product.
If customers have special requirements for filters, air volume or product size, they can also be adjusted based on the actual conditions of the equipment.
For example:
Ultra-thin EFU
HEPA EFU
ULPA EFU
High air volume EFU
Device customization EFU
Specific product configurations need to be determined based on actual application conditions.
18. Frequently Asked Questions
Are EFU and HEPA the same product?
no. EFU is the equipment-end fan filter unit, HEPA is a high-efficiency filter, and HEPA can be used as the filter component of EFU.
Can EFU use ULPA filters?
Can. Whether to use ULPA needs to be determined based on specific cleanliness requirements, filter resistance and equipment operating conditions.
Will HEPA filters affect EFU air volume?
meeting. The filter has a certain resistance, so it is necessary to select a matching fan and motor based on the filter resistance.
Can EFU filters be customized?
It can be matched according to product structure, installation space, filtration requirements and air volume requirements.
Can HEPA be installed on ultra-thin EFU?
Can be designed according to specific product structure and filter size. The actual height needs to be determined based on air volume, air pressure, filters and internal structure.
Does Aili Industrial produce its own EFU filters?
Aili Industrial's production system covers filters, motors, fans, automatic control system software and hardware, sheet metal and complete machine assembly, and can be integrated around EFU products.
