Replacement Air Filters – HVAC, AHU, FCU, HEPA and Industrial Filters

Replacement Air Filters are filtration products used to replace existing filters in HVAC systems, Air Handling Units, Fan Coil Units, fresh-air systems, cleanrooms, industrial ventilation equipment and other air-treatment systems.

Air filters gradually accumulate dust and airborne contaminants during operation. As loading increases, pressure drop can rise, airflow may decrease and filtration performance can be affected. Filters can also require replacement because of physical damage, moisture exposure, seal failure, media deterioration or project maintenance requirements.

VIETPHAT supplies replacement filters including Pre Filters, Panel Filters, Pleated Filters, Bag Filters, Pocket Filters, Fine Air Filters, Compact Filters, V-Bank Filters, Activated Carbon Filters, HEPA Filters and custom-size filters for commercial, industrial, healthcare, pharmaceutical, food, electronics, semiconductor, data-center and cleanroom applications.

What Are Replacement Air Filters?

Replacement Air Filters are new filters selected to replace existing air filters while maintaining or restoring the intended filtration performance, airflow and system compatibility.

A replacement filter should normally match or appropriately improve the original filter in terms of:

• Physical dimensions.
• Filter type.
• Efficiency.
• Rated airflow.
• Initial pressure drop.
• Recommended final pressure drop.
• Media construction.
• Frame construction.
• Seal configuration.
• Installation direction.

Choosing a replacement based only on external dimensions can lead to poor system performance.

Why Do Air Filters Need Replacement?

Most air filters have a finite service life.

Replacement may be required because of:

• Dust loading.
• Increasing differential pressure.
• Reduced airflow.
• Damaged media.
• Damaged frames.
• Broken or compressed gaskets.
• Moisture damage.
• Microbial or hygiene concerns.
• Gas-phase media saturation.
• Failed HEPA integrity testing.
• Facility maintenance procedures.

Why Correct Replacement Filter Selection Matters

An incorrect replacement filter can cause several problems.

Examples include:

• Air bypass around the filter.
• Higher-than-expected pressure drop.
• Reduced HVAC airflow.
• Increased fan energy consumption.
• Insufficient particle filtration.
• Premature filter loading.
• Incorrect sealing.
• Reduced cleanroom performance.
• Shorter filter service life.

Main Types of Replacement Air Filters

1. Replacement Pre Air Filters

Replacement Pre Filters are used as the first filtration stage in AHUs, HVAC units and fresh-air systems.

They help remove larger particles before air reaches downstream Fine, Compact or HEPA Filters.

Common constructions include:

• Synthetic panel filters.
• Pleated pre filters.
• Washable filters where designed for reuse.
• Filter media pads.
• Filter rolls.

2. Replacement Panel Air Filters

Replacement Panel Filters are commonly used in general ventilation and primary filtration applications.

They may be supplied with:

• Galvanized steel frames.
• Aluminum frames.
• Plastic frames.
• Cardboard frames for selected disposable products.

3. Replacement Pleated Air Filters

Replacement Pleated Filters provide additional media area compared with flat filters.

They may be used in:

• Commercial HVAC systems.
• Industrial ventilation systems.
• AHUs.
• FCUs where compatible.
• Fresh-air units.

4. Replacement Bag Filters

Replacement Bag Filters or Pocket Filters are widely used in AHUs as intermediate or fine filtration stages.

Important replacement parameters include:

• Width.
• Height.
• Pocket length.
• Number of pockets.
• Filter efficiency.
• Rated airflow.
• Initial pressure drop.

5. Replacement Fine Air Filters

Replacement Fine Air Filters are used where improved particulate filtration is required.

Depending on tested ISO 16890 performance, they may be classified as:

• ePM10.
• ePM2.5.
• ePM1.

6. Replacement Compact Air Filters

Replacement Compact Filters use pleated media in rigid housings and are common in high-performance HVAC systems.

Before replacement, confirm:

• Filter depth.
• Housing dimensions.
• Rated airflow.
• Efficiency.
• Seal location.
• Airflow direction.

7. Replacement V-Bank Air Filters

Replacement V-Bank Filters are used in high-capacity commercial and industrial HVAC applications.

They may provide:

• Large media area.
• High airflow capacity.
• Compact depth.
• Higher fine-particle filtration.
• Suitable long-term performance in continuously operated systems.

8. Replacement Activated Carbon Filters

Replacement Activated Carbon Filters are used where selected odors, VOCs or gaseous contaminants require control.

Replacement media should be selected according to the target contaminant rather than simply matching physical size.

Possible media include:

• Virgin activated carbon.
• Impregnated activated carbon.
• Blended adsorbent media.
• Chemisorption media.

9. Replacement HEPA Filters

Replacement HEPA Filters are used in cleanrooms, hospitals, pharmaceutical facilities, food plants, laboratories and other controlled environments.

Common HEPA classifications include:

• H13.
• H14.

HEPA replacement requires more technical verification than ordinary general-ventilation filters.

10. Replacement ULPA Filters

Replacement ULPA Filters may be used in semiconductor, microelectronics and highly controlled cleanroom applications.

Replacement should consider:

• Filter class.
• Rated airflow.
• Pressure drop.
• Frame design.
• Seal type.
• FFU or terminal housing compatibility.
• Integrity testing requirements.

Replacement Air Filter Types at a Glance

Replacement Filter	Typical Application	Main Selection Factors
Pre Filter	AHU / Fresh Air / HVAC	Size, efficiency, airflow, pressure drop
Panel Filter	Commercial / Industrial HVAC	Frame, media, dimensions
Pleated Filter	AHU / FCU / Ventilation	Pleat depth, efficiency, airflow
Bag Filter	AHU	Pockets, depth, efficiency, airflow
Fine Filter	HVAC / AHU	ISO 16890 performance, pressure drop
Compact / V-Bank Filter	High-capacity HVAC	Media area, airflow, depth, seal
Carbon Filter	Odor / VOC / gas-phase control	Target contaminant, media capacity
HEPA Filter	Cleanroom / Hospital / Pharma	Class, seal, integrity, airflow
ULPA Filter	Semiconductor / Ultra-clean areas	Class, FFU compatibility, integrity

Replacement Filters for HVAC Systems

HVAC systems use filters to protect equipment and reduce airborne contaminants in supply, return and outdoor air.

Replacement HVAC filters may include:

• Pre Filters.
• Pleated Filters.
• Bag Filters.
• Fine Filters.
• Compact Filters.
• V-Bank Filters.
• Carbon Filters.

Replacement should match the fan and system pressure-drop capability.

Replacement Filters for AHUs

Air Handling Units frequently use multiple filtration stages.

A typical AHU replacement sequence may include:

• Pre-filter replacement.
• Bag or Fine Filter replacement.
• Compact or V-Bank Filter replacement.
• Carbon filter replacement where applicable.
• HEPA final-filter replacement in selected systems.

Changing one stage can affect the loading and pressure drop of the other stages.

Replacement Filters for FCUs

Fan Coil Units generally use compact, low-resistance filters.

Typical replacement FCU filters include:

• Synthetic filters.
• Mesh filters.
• Panel filters.
• Shallow pleated filters.

Because FCU fans usually have limited static-pressure capability, installing a much higher-resistance replacement filter can reduce cooling airflow.

Replacement Filters for Fresh-Air Units

Fresh-air units often receive high dust loading because they process outdoor air.

Replacement filters may need to address:

• PM10.
• PM2.5.
• PM1.
• Pollen.
• Road dust.
• Industrial pollution.

Facilities in polluted urban or industrial locations may benefit from suitable higher-efficiency upstream filtration where the system can accommodate the pressure drop.

Replacement Filters for Commercial Buildings

Commercial buildings commonly require replacement filters for:

• Office AHUs.
• Hotel AHUs.
• Shopping mall HVAC systems.
• Airport ventilation systems.
• Schools.
• Mixed-use developments.
• FCUs.

Typical replacement filters include Pre, Bag, Fine, Compact, V-Bank and Carbon Filters.

Replacement Filters for Manufacturing Plants

Industrial facilities may require replacement filtration for:

• General production AHUs.
• Fresh-air systems.
• Process-support HVAC.
• Controlled production spaces.
• Equipment cooling systems.

Heavy process dust should generally be handled by dedicated process dust collectors rather than ordinary HVAC replacement filters.

Replacement Filters for Hospitals

Healthcare facilities may use different filter efficiencies depending on room function.

Replacement filters may include:

• Pre Filters.
• Fine Filters.
• Compact Filters.
• HEPA Filters.
• Activated Carbon or molecular filters for selected applications.

HEPA replacement in critical healthcare areas may require installed integrity testing and verification of sealing.

Replacement Filters for Pharmaceutical Plants

Pharmaceutical facilities may use replacement:

• Pre Filters.
• Fine Filters.
• HEPA Filters.
• ULPA Filters in selected applications.
• Molecular Filters.

Filter class alone does not ensure GMP compliance or cleanroom classification. Replacement must remain consistent with the qualified HVAC and contamination-control system.

Replacement Filters for Food Factories

Food factories may require replacement filters in:

• General HVAC systems.
• High-care areas.
• Packaging areas.
• Cold rooms.
• Fresh-air units.
• Selected HEPA-filtered zones.

Moisture resistance and hygienic maintenance can be important in food-processing environments.

Replacement Filters for Semiconductor Plants

Semiconductor facilities may require highly controlled replacement of:

• Fine upstream filters.
• HEPA Filters.
• ULPA Filters.
• FFU Filters.
• AMC Filters.
• Molecular Filters.

Physical dimensions, seal type, filter class, integrity and airflow performance are critical in these environments.

Replacement Filters for Data Centers

Data centers may use replacement filters in:

• AHUs.
• CRAC units.
• CRAH units.
• Fresh-air systems.
• Air-side economizer systems.

Pressure drop is particularly important because data-center cooling systems depend on continuous high airflow.

Replacement Filters for Paint Booths

Paint booths require specialized replacement filtration for different positions.

Typical products include:

• Intake Pre Filters.
• Ceiling Filters.
• F5 / F6 legacy-grade ceiling media.
• Fiberglass Paint Arrestors.
• Floor Filters.
• Paper Paint Filters.

Paint booth exhaust filters should be selected for overspray loading and should not automatically be replaced with ordinary HVAC filters.

Replacement Filters for Cleanrooms

Cleanrooms may require replacement filters at several stages:

• AHU Pre Filters.
• Fine Filters.
• HEPA Filters.
• ULPA Filters.
• Terminal Filters.
• FFU Filters.

Cleanroom performance depends on the complete HVAC and contamination-control system, not filter class alone.

Replacement HEPA Filters for Cleanrooms

Replacing a HEPA filter in a cleanroom requires careful attention to:

• Filter dimensions.
• H13 or H14 class.
• Rated airflow.
• Initial resistance.
• Gasket or gel seal.
• Knife-edge dimensions.
• Housing compatibility.
• Integrity testing.

Replacement Filters for FFUs

Fan Filter Units commonly use HEPA or ULPA Filters.

Before replacement, verify:

• FFU model.
• Filter outer dimensions.
• Filter depth.
• Rated airflow.
• Filter class.
• Pressure drop.
• Seal type.
• Frame material.

Replacement Terminal HEPA Filters

Terminal HEPA Filters are installed close to the cleanroom supply point.

Replacement should maintain:

• Correct sealing.
• Correct mounting.
• Specified filter class.
• Required airflow.
• System integrity.

Replacement Air Filters and ISO 16890

ISO 16890 is widely used for classifying general ventilation filters according to particulate matter efficiency.

Main groups include:

• ISO Coarse.
• ePM10.
• ePM2.5.
• ePM1.

When replacing older filters, ISO 16890 performance can provide useful modern technical data for general ventilation applications.

Replacement G4, M5, M6, F7, F8 and F9 Filters

Many existing HVAC systems still specify former EN 779 classes such as:

• G4.
• M5.
• M6.
• F7.
• F8.
• F9.

These designations remain common in replacement markets.

However, replacing an old G4, F7, F8 or F9 filter should not rely solely on the legacy class name. Dimensions, airflow, pressure drop and current tested performance should also be checked.

Can an F7 Filter Be Replaced with an ePM1 Filter?

Potentially, but there is no exact universal one-to-one conversion between former EN 779 classes and ISO 16890 classifications.

The replacement should be based on tested product data and HVAC system requirements.

Replacement HEPA Filters and EN 1822

HEPA Filters may be classified and tested according to EN 1822.

Common classes include:

• H13.
• H14.

For replacement, the original filter's tested performance should be confirmed rather than assuming that all products carrying the same generic HEPA name are interchangeable.

Replacement HEPA Filters and ISO 29463

ISO 29463 provides an international framework for high-efficiency particulate filter classification and testing.

For critical applications, technical documentation and individual testing requirements should be reviewed during replacement selection.

H13 Replacement Filters

H13 Replacement Filters are used in many cleanroom, pharmaceutical, healthcare and industrial applications.

Important specifications include:

• Dimensions.
• Rated airflow.
• Initial pressure drop.
• Frame material.
• Gasket or gel seal.
• Filter test data.

H14 Replacement Filters

H14 Replacement Filters provide a higher HEPA classification than H13.

However, replacing H13 with H14 should not be done automatically because the higher filter class may have different pressure-drop and system implications.

Can a Higher-Efficiency Filter Replace the Existing Filter?

Sometimes, but the upgrade must be checked technically.

A higher-efficiency filter can have:

• Higher initial pressure drop.
• Different loading behavior.
• Different frame depth.
• Different sealing requirements.
• Different fan requirements.

Before upgrading, verify that the HVAC or AHU fan can maintain the required airflow.

Why Dimensions Alone Are Not Enough

Two filters can have identical outer dimensions but very different performance.

They may differ in:

• Efficiency.
• Rated airflow.
• Media area.
• Initial resistance.
• Dust-holding capacity.
• Frame design.
• Seal type.

For this reason, replacement filters should be selected using both physical and technical specifications.

Nominal Size vs Actual Filter Size

Some filter specifications use nominal dimensions while the actual manufactured size is slightly smaller.

For accurate replacement, it is preferable to measure the existing filter directly.

Measure:

Width × Height × Depth (W × H × D)

Dimensions should normally be recorded in millimeters for procurement accuracy.

How to Measure a Replacement Air Filter

Step 1 – Measure Width

Measure the horizontal dimension of the existing filter frame.

Step 2 – Measure Height

Measure the vertical frame dimension.

Step 3 – Measure Depth

Measure the thickness or installation depth.

Step 4 – Check the Airflow Direction

Many filters have an airflow arrow on the frame.

Step 5 – Check Frame and Seal

Inspect whether the filter has:

• No gasket.
• Single-side gasket.
• Double-side gasket.
• Gel seal.
• Knife-edge configuration.

Replacement Bag Filter Measurements

For a Bag Filter, also confirm:

• Number of pockets.
• Pocket length.
• Frame thickness.
• Media construction.
• Filter class.

Replacement HEPA Filter Measurements

For HEPA Filters, also confirm:

• Frame dimensions.
• Media pack depth.
• Separator or mini-pleat design.
• Gasket location.
• Gel seal dimensions.
• Knife-edge position.

Filter Rated Airflow

Rated Airflow is a critical replacement parameter.

A filter should be operated within its intended airflow range.

Using an undersized filter at excessive airflow can:

• Increase pressure drop.
• Reduce service life.
• Increase face velocity.
• Change filtration behavior.

Replacement Filter Pressure Drop

Pressure drop is the resistance created as air passes through the filter.

Key parameters include:

• Initial pressure drop.
• Average operating pressure drop.
• Recommended final pressure drop.

Why Initial Pressure Drop Matters

Replacing an existing filter with a product having significantly higher resistance can affect system airflow.

This is particularly important for:

• FCUs.
• CRAC units.
• CRAH units.
• Low-static-pressure AHUs.
• FFUs.

Recommended Final Pressure Drop

The final replacement resistance should be based on:

• Filter manufacturer recommendations.
• Available fan static pressure.
• Required airflow.
• Energy considerations.
• Facility maintenance requirements.

Differential Pressure Monitoring

Differential pressure gauges and sensors can help determine when particulate filters are becoming loaded.

They are useful for monitoring:

• Bag Filters.
• Fine Filters.
• Compact Filters.
• V-Bank Filters.
• HEPA Filters.

When Should an Air Filter Be Replaced?

There is no universal replacement interval for every air filter.

Replacement may be required when:

• Pressure drop reaches the approved limit.
• Airflow decreases.
• Dust loading becomes excessive.
• Media is damaged.
• Frame is damaged.
• Gasket or seal fails.
• Filter becomes wet or contaminated.
• HEPA filter fails integrity testing.
• Carbon media reaches its adsorption capacity.

Should Air Filters Be Replaced on a Fixed Schedule?

Fixed maintenance schedules can be useful operationally, but filter condition can vary significantly with:

• Outdoor air quality.
• Operating hours.
• Airflow.
• Dust loading.
• Season.
• Process conditions.

Where practical, differential-pressure monitoring and condition-based maintenance can provide a more accurate replacement strategy.

Can Replacement Air Filters Be Washed?

Only filters specifically designed as washable should be cleaned and reused.

Most:

• Pleated Filters.
• Bag Filters.
• Fine Filters.
• Compact Filters.
• V-Bank Filters.
• HEPA Filters.
• ULPA Filters.

are normally disposable.

Can HEPA Filters Be Washed?

No. Standard HEPA Filters are generally not designed to be washed.

Washing may damage:

• Filter media.
• Pleats.
• Separators.
• Sealants.
• Frame integrity.

Replacement Carbon Filter Service Life

Carbon filters require a different replacement strategy from particulate filters.

Adsorbent media can become saturated without a significant increase in pressure drop.

Replacement may therefore be based on:

• Expected media life.
• Target gas concentration.
• Operating hours.
• Media weight.
• Contact time.
• Humidity.
• Temperature.
• Breakthrough monitoring.

Can Odor Be Used to Determine Carbon Filter Replacement?

Odor breakthrough can sometimes indicate that adsorption performance has declined, but it should not be the only replacement criterion in critical systems.

Some hazardous or corrosive gases may not provide a reliable odor warning.

Replacement Air Filter Sealing

Correct sealing is critical because air can bypass a high-efficiency filter if the frame or gasket does not fit correctly.

Potential bypass causes include:

• Incorrect dimensions.
• Compressed gasket.
• Damaged gasket.
• Loose filter clips.
• Distorted frame.
• Damaged housing.

Replacement HEPA Filter Integrity Testing

In cleanrooms and other critical environments, newly installed HEPA Filters may require integrity testing according to approved procedures.

Testing can help identify:

• Media leaks.
• Frame leaks.
• Seal leaks.
• Housing leaks.
• Installation defects.

Replacement Air Filters and Energy Consumption

Filter pressure drop contributes to fan energy consumption.

For continuously operated HVAC systems, energy can be an important part of total filter cost.

A life-cycle comparison should consider:

• Initial resistance.
• Average operating resistance.
• Filter efficiency.
• Dust-holding capacity.
• Service life.
• Replacement frequency.
• Fan energy consumption.

Low Pressure Drop Replacement Filters

Low-resistance filters can help reduce fan energy, but selection should not be based on initial pressure drop alone.

The filter must still provide the required:

• Efficiency.
• Dust-holding capacity.
• Mechanical strength.
• Service life.
• System compatibility.

High-Capacity Replacement Air Filters

High-capacity Bag, Compact and V-Bank Filters may be useful in applications with:

• High outdoor dust loading.
• Continuous operation.
• Large airflow volumes.
• Long maintenance intervals.
• Limited opportunities for filter replacement.

Replacement Filters by Brand

Replacement filters do not always need to be supplied by the original equipment brand, provided the alternative filter is technically compatible and meets the required specifications.

Before selecting an equivalent replacement, compare:

• Dimensions.
• Efficiency.
• Rated airflow.
• Pressure drop.
• Media construction.
• Frame.
• Seal.
• Applicable testing and certification.

OEM vs Equivalent Replacement Air Filters

Criteria	OEM Replacement	Equivalent Replacement
Brand	Original manufacturer	Alternative manufacturer
Dimensions	Original specification	Must match installation
Efficiency	Original specification	Must meet required performance
Pressure Drop	Original design	Must be checked for compatibility
Seal	Original design	Must match housing
Selection Basis	Part number	Technical equivalence

Can a Different Brand Replace the Existing Filter?

Yes, in many applications a technically compatible filter from another manufacturer can be used.

However, the replacement should meet the required dimensions and performance rather than being selected only because it looks similar.

Custom Replacement Air Filters

Older AHUs, imported equipment and custom HVAC systems may use non-standard filter dimensions.

Depending on filter construction, VIETPHAT can support custom requirements for:

• Width.
• Height.
• Depth.
• Filter efficiency.
• Media type.
• Frame material.
• Number of pockets.
• Pocket length.
• Gasket position.
• Seal configuration.

Replacement Filters for Discontinued Models

If an original filter model is discontinued, a replacement can often be developed using:

• Existing filter dimensions.
• Old technical datasheet.
• Part number.
• Equipment model.
• Photographs.
• Filter class.
• Airflow.
• Pressure drop.

Replacement Filter Part Numbers

A manufacturer part number can make filter identification easier, but it should be supported with technical data whenever possible.

Some filter part numbers are specific to:

• Dimensions.
• Efficiency.
• Frame material.
• Seal type.
• Testing option.

How to Select Replacement Air Filters

1. Identify the Existing Filter Type

Determine whether it is:

• Pre Filter.
• Panel Filter.
• Pleated Filter.
• Bag Filter.
• Fine Filter.
• Compact Filter.
• V-Bank Filter.
• Carbon Filter.
• HEPA Filter.
• ULPA Filter.

2. Measure the Existing Filter

Record:

Width × Height × Depth

3. Confirm the Filter Efficiency

Check the label, datasheet or project specification.

4. Confirm Rated Airflow

Identify the airflow through each filter.

5. Check Pressure Drop

Review initial and recommended final resistance.

6. Check Frame Material

Common materials include:

• Galvanized steel.
• Aluminum.
• Plastic.
• Cardboard.

7. Check Seal Configuration

Especially important for HEPA and ULPA Filters.

8. Identify the Application

Examples:

• Office HVAC.
• Factory AHU.
• Hospital.
• Pharmaceutical cleanroom.
• Food plant.
• Semiconductor FFU.
• Data center.
• Paint booth.

9. Determine Whether an Upgrade Is Required

Efficiency upgrades should be evaluated against fan and housing capability.

10. Compare Life-Cycle Cost

Do not compare purchase price alone.

Important Replacement Air Filter Specifications

Parameter	Information Required
Dimensions	W × H × D in mm
Filter Type	Panel / Bag / Fine / Compact / HEPA / etc.
Filter Efficiency	ISO Coarse / ePM10 / ePM2.5 / ePM1 / H13 / H14 / ULPA
Rated Airflow	m³/h
Initial Pressure Drop	Pa
Final Pressure Drop	Pa if specified
Media	Synthetic / Glass Fiber / Carbon / specified media
Frame	GI / Aluminum / Plastic / Cardboard
Seal	No gasket / Gasket / Gel Seal
Equipment	AHU / FCU / FFU / CRAC / CRAH
Application	Commercial / Industrial / Cleanroom
Quantity	Required replacement quantity

Common Replacement Air Filter Problems

Replacement Filter Does Not Fit

This usually results from confusing nominal size with actual dimensions or measuring incorrectly.

Airflow Drops after Replacement

The new filter may have higher resistance than the original filter.

Filter Moves inside the Housing

This can indicate incorrect dimensions or insufficient clamping.

Dust Appears Downstream

Potential causes include:

• Air bypass.
• Damaged media.
• Incorrect filter efficiency.
• Incorrect installation direction.

Replacement Filter Loads Too Quickly

Potential causes include:

• Insufficient pre-filtration.
• Higher-than-expected dust loading.
• Incorrect media area.
• Excessive airflow.
• Process contamination entering the HVAC system.

New HEPA Filter Fails Integrity Testing

Potential causes can include media damage, seal leakage, handling damage or incorrect installation.

Carbon Filter Does Not Remove the Target Odor

The media may not be suitable for the actual gas or VOC.

How to Extend Replacement Filter Service Life

• Use appropriate upstream pre-filtration.
• Keep outdoor-air intakes clean.
• Monitor differential pressure.
• Operate within rated airflow.
• Prevent air bypass.
• Maintain coils and AHUs.
• Control process dust at source.
• Select sufficient media area.
• Use suitable gas-phase media for the target contaminant.

Life-Cycle Cost of Replacement Air Filters

The lowest-cost replacement filter is not always the lowest-cost option over its operating life.

Life-cycle cost may include:

• Initial purchase price.
• Average pressure drop.
• Fan energy consumption.
• Service life.
• Replacement frequency.
• Maintenance labor.
• Disposal cost.
• Impact on downstream equipment.
• Downtime.
• Testing cost for critical filters.

Replacement Air Filter Supplier in Vietnam – VIETPHAT

VIETPHAT supplies replacement filters for existing HVAC, AHU, FCU, cleanroom, industrial and specialized air-filtration systems.

We can support replacement selection based on:

• Existing filter dimensions.
• Existing brand.
• Part number.
• Filter efficiency.
• Airflow.
• Pressure drop.
• Frame material.
• Seal type.
• Equipment model.
• Application.

VIETPHAT Replacement Air Filter Product Range

• Replacement Pre Filters.
• Replacement Panel Filters.
• Replacement Pleated Filters.
• Replacement Bag Filters.
• Replacement Pocket Filters.
• Replacement Fine Filters.
• Replacement Compact Filters.
• Replacement V-Bank Filters.
• Replacement Activated Carbon Filters.
• Replacement H13 HEPA Filters.
• Replacement H14 HEPA Filters.
• Replacement ULPA Filters.
• Replacement FFU Filters.
• Replacement AHU Filters.
• Replacement FCU Filters.
• Replacement CRAC Filters.
• Replacement CRAH Filters.
• Replacement Paint Booth Filters.
• Custom Replacement Air Filters.

Applications of VIETPHAT Replacement Air Filters

• Commercial buildings.
• Factories.
• Hospitals.
• Pharmaceutical plants.
• Food factories.
• Electronics factories.
• Semiconductor plants.
• Data centers.
• Cleanrooms.
• Hotels.
• Shopping malls.
• Airports.
• Paint booths.
• Warehouses.
• Industrial HVAC systems.

Information Required for a Replacement Air Filter Quotation

Required Information	Example
Dimensions	W × H × D in mm
Existing Filter Type	Bag / Fine / HEPA / V-Bank
Existing Filter Class	G4 / F7 / ePM1 / H13 / H14
Rated Airflow	m³/h
Pressure Drop	Pa if available
Frame Material	GI / Aluminum / Plastic
Seal Type	Gasket / Gel / None
Existing Brand	Brand name if available
Part Number	Existing P/N if available
Equipment	AHU / FCU / FFU / CRAC / CRAH
Application	Factory / Hospital / Cleanroom / etc.
Quantity	Number of filters

Frequently Asked Questions About Replacement Air Filters

How Do I Find the Correct Replacement Air Filter?

Identify the existing filter type, measure Width × Height × Depth and confirm efficiency, airflow, pressure drop, frame and seal configuration.

Can I Replace an Air Filter with a Different Brand?

Yes, provided the alternative filter is technically compatible in dimensions, efficiency, airflow, pressure drop, sealing and application requirements.

Do Replacement Filters Need the Same Part Number?

Not always. A technically equivalent replacement may have a different part number, but the relevant performance specifications should match.

Can I Replace a G4 Filter with an F7 Filter?

Only after checking system airflow and fan static pressure. A higher-efficiency filter may introduce more resistance.

Can I Replace an F7 Filter with an ePM1 Filter?

Potentially, but former EN 779 classes and ISO 16890 classifications are not exact one-to-one equivalents. Product test data should be compared.

Can I Upgrade from H13 to H14?

Possibly, but the H14 filter must be compatible with airflow, pressure drop, housing and seal requirements. H14 should not automatically replace H13 unless required.

How Often Should Replacement Air Filters Be Changed?

Replacement frequency depends on differential pressure, dust loading, airflow, operating hours, filter condition and application requirements.

Can Air Filters Be Replaced Based Only on Time?

Fixed schedules can be useful, but condition-based replacement using differential pressure and inspection is often more accurate for particulate filters.

Can Replacement Air Filters Be Washed?

Only filters specifically designed as washable should be reused. Most Fine, Bag, Compact, V-Bank, HEPA and ULPA Filters are disposable.

Can HEPA Filters Be Washed and Reused?

No. Standard HEPA Filters are generally not washable.

How Do I Know if a Carbon Filter Needs Replacement?

Carbon media may require replacement based on expected media life, operating hours, target gas concentration, monitoring or breakthrough analysis rather than pressure drop alone.

Why Is My New Filter Causing Lower Airflow?

The replacement filter may have higher resistance than the original, or it may be incorrectly sized, loaded, installed or incompatible with the fan system.

What Is the Difference Between Nominal and Actual Filter Size?

Nominal dimensions are rounded identification sizes, while actual dimensions are the true manufactured dimensions. Actual measurements should be used when replacing filters.

Can VIETPHAT Produce Custom Replacement Filters?

Yes. Depending on filter construction, VIETPHAT can support custom dimensions, efficiency, media, frame materials, pocket configuration and seal arrangements.

Can VIETPHAT Replace Imported Filter Brands?

VIETPHAT can evaluate replacement requirements based on existing filter dimensions, part numbers, technical data and application to identify suitable alternatives where available.

What Information Should I Send for a Replacement Filter Quotation?

Please provide filter photographs, Width × Height × Depth, existing filter class, brand, part number, airflow, pressure drop if available, frame material, seal type, equipment model and quantity.

Contact VIETPHAT for Replacement Air Filters

For technical consultation, replacement selection or quotation for Replacement Air Filters for HVAC, AHU, FCU, cleanroom and industrial systems, please contact VIETPHAT:

• Zalo / Hotline: 0971 344 344
• Sales: 0827 077 078
• Sales: 0829 077 078
• Email: sales@vietphat.com
• Website: www.vietphat.com

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