Which filters are best for your air handling unit in autumn? Discover what installers recommend

date_range 12 October 2025
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Why it’s important to replace ventilation filters in autumn

Dust, pollen, soot and other fine particles are often invisible to the eye (PM2.5 / PM1), yet these are the ones that most affect both your health and the efficiency of your system. Choosing the right filters for your ventilation unit improves indoor air quality and extends the lifespan of the device.

1. G4 class filters – the main protection for your ventilation unit

G4 class filters are designed to protect the heat exchanger and fan blades from larger dust particles. The air channels in the heat exchanger are usually about 2–4 mm wide, so a G4 filter captures particles larger than 20–30 microns.

  • Suitable for clean environments – rural areas with low air pollution.
  • Service life: around 6–8 months.

Note: Mesh or fabric filters should be vacuumed every 2–3 months and replaced after several cleanings – roughly every 6–8 months.

Brink Flair 325/400 G4+G4...

Brink Flair 325/400 G4+G4 Filter set (Standard)

Price 6.30 €

Ex VAT: 6.30 €

Manufacturer of MVHRBrink
ManufacturerCleanFilter
Air handling unit
  • Brink Flair 325
  • Brink Flair 400
Filter dimensions245x510x5
Class EN779G4+G4
Class ISO16890Coarse 65%
Protection levelBasic: larger solid particles, dust, fluff.
Quantity of filters2
Advantages
  • Lower running costs – lower filter price, lower energy use, and usually longer time between replacements than higher-efficiency filters.
  • Made in the EU – reliable quality and strict safety standards
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
Manufacturer product number1669551
Remarksℹ️ This filter set protects the MVHR from larger particles. For finer filtration (pollen, smog), use an F7 supply air filter, available in our shop.
Zehnder ComfoAir Q 350/450/600 G4+G4 Filter set

Zehnder ComfoAir Q 350/450/600 G4+G4 Filter set (Standard)

Price 13.23 €

Ex VAT: 13.23 €

Manufacturer of MVHRZehnder
ManufacturerCleanFilter
Air handling unit
  • ComfoAir Q 450
  • ComfoAir Q 350
  • ComfoAir Q 600
Filter dimensions500x159x22
Class EN779G4+G4
Class ISO16890Coarse 75%
Protection levelBasic: larger solid particles, dust, fluff.
Quantity of filters2
Advantages
  • Lower running costs – lower filter price, lower energy use, and usually longer time between replacements than higher-efficiency filters.
  • Made in the EU – reliable quality and strict safety standards
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
  • Premium replacement filter – tested quality, airtight construction with fully bonded media, and reliable performance
Manufacturer product number
  • 400502012
  • 400502014
Remarks⚠️ Remarks: ComfoAir ≠ ComfoAir Q. Different dimensions, not interchangeable. Check your ventilation unit model/version before ordering.
Blauberg KOMFORT EC D5 180 G4+G4 filtrų komplektas (Standartinis)

Blauberg KOMFORT EC D5 180 G4+G4 Filter set (Standard)

Price 10.61 €

Ex VAT: 10.61 €

Manufacturer of MVHRBlauberg
ManufacturerCleanFilter
Air handling unit
  • KOMFORT EC D5 180
  • KOMFORT D5 180
Filter dimensions214x186x18
Class EN779G4+G4
Class ISO16890Coarse 75%
Protection levelBasic: larger solid particles, dust, fluff.
Quantity of filters2
Advantages
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
  • Lower running costs – lower filter price, lower energy use, and usually longer time between replacements than higher-efficiency filters.
  • Made in the EU – reliable quality and strict safety standards
Remarks
  • ℹ️ Additional F7/F8 supply air filter is sold separately and available in our shop.
  • ℹ️ This MVHR unit has 3 filter slots: Supply air: G4 (mandatory) + optional F7/F8 (for pollen, smog, fine particles). Extract air: G4 (mandatory) 👉 The two G4 filters are always required. The F7/F8 filter is optional for extra protection.
PLUGGIT Avent P300 G4+G4...

PLUGGIT Avent P300 G4+G4 Filter set (Standard)

Price 15.07 €

Ex VAT: 15.07 €

Manufacturer of MVHRPluggit
ManufacturerCleanFilter
Air handling unitPLUGGIT Avent P300
Filter dimensions350x160x46
Class EN779G4+G4
Class ISO16890Coarse 75%
Protection levelBasic: larger solid particles, dust, fluff.
Quantity of filters2
Advantages
  • Lower running costs – lower filter price, lower energy use, and usually longer time between replacements than higher-efficiency filters.
  • Made in the EU – reliable quality and strict safety standards
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
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2. The more air-permeable the filter, the lower the airflow resistance

More permeable filters put less strain on the fans, which reduces electricity consumption and extends the lifespan of your ventilation unit.

Average filter service life:

  • G4 – 6–8 months
  • M5 – 5–7 months
  • F7 – 4–6 months
  • Activated carbon – 3–4 months

If your surroundings are clean and you want to save on costs, a G4 filter will be sufficient.

3. F7 filters for ventilation units – essential if neighbours use solid fuel heating

An F7 class filter captures fine particles of carbon, soot, and combustion residues. If you notice stronger odours, use an activated carbon filter, which absorbs smells and volatile organic compounds (VOCs).

➡️ Read more about activated carbon filters here

Wolf CWL-2-325/400 1xF7...

Wolf CWL-2-325/400 1xF7 Filter (Smog&Pollen)

Price 19.94 €

Ex VAT: 19.94 €

Manufacturer of MVHRWOLF
ManufacturerCleanFilter
Air handling unit
  • Wolf CWL-2-325
  • Wolf CWL-2-400
Filter dimensions245x510x22
Class EN779F7
Class ISO16890ePM1 70%
Protection levelHigh: fine particles, dust, pollen, mold spores, combustion particles, smog particles, insecticide dust.
Quantity of filters1
Advantages
  • Maximum protection – ePM1 70% removes up to 40% more smog, pollen and fine dust than standard filters (50–60%).
  • Made in the EU – reliable quality and strict safety standards
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
Manufacturer product number1669552
Remarksℹ️ This is a supply air filter. For extract air filtration, please order a separate G4/M5 filter (available in our shop).
Zehnder ComfoAir 180 F7 G4 filter set

ComfoAir 180 / WHR 918 F7+G4 Filter set (Efficient)

Price 13.34 €

Ex VAT: 13.34 €

Manufacturer of MVHRZehnder
ManufacturerCleanFilter
Air handling unit
  • ComfoAir 180
  • WHR 918
Filter dimensions124x235x25
Class EN779F7+G4
Class ISO16890ePM1 65%
Protection levelHigh: fine particles, dust, pollen, mold spores, combustion particles, smog particles, insecticide dust.
Quantity of filters2
Advantages
  • High filtering efficiency – ePM1 65% (most analog filters from China – ePM10 70%).
  • More protection from tiny particles (PM1) – ePM1 65% filtration (many original filters are around ePM1 50–55%).
  • Captures fine dust and combustion particles – reduces soot and traffic-related particles through mechanical filtration, not relying only on electrostatic charge.
  • Easier airflow for your ventilation unit – up to 3× lower initial resistance compared to our previous media (internal lab tests).
  • Verified performance – ISO 16890 tested, made in the EU.
Manufacturer product number400100091
Domekt R 250 F / R 400 F (up to 2021-03) 1xF7/AC Activated carbon filter (Odor) CleanFilter - 1

Domekt R 250 F / R 400 F (up to 2021-03) 1xF7/AC Activated carbon...

Price 18.72 €

Ex VAT: 18.72 €

Manufacturer of MVHRKomfovent
ManufacturerCleanFilter
Air handling unit
  • Domekt R 250 F (Rego 250 PE)
  • Domekt R 400 F (Rego 400 PE)
Filter dimensions278x258x46
Class EN779F7/AC
Class ISO16890ePM2.5 60%
Protection levelParticles and odors: fine particles, dust, pollen, mold spores, combustion particles, volatile particles, NOx, O3 gases.
Quantity of filters1
Advantages
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
  • Absorbs volatile particles (odors) and harmful gases as NOx, O3, etc.
  • Made in the EU – reliable quality and strict safety standards
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
Remarks
  • ⚠️ Not suitable for Domekt R 400 F C6M model (from 03/2021). Please check model or filter size before ordering.
  • 🌟 High-quality replacement filter: made from certified materials (Germany, SANDLER AG) with tested performance. Provides reliable air filtration and optimal service life.
SIBER DF EVO / EVO2 F7+G4...

SIBER DF EVO / EVO2 F7+G4 Filter (Smog&Pollen)

Price 12.04 €

Ex VAT: 12.04 €

Manufacturer of MVHRSiber
ManufacturerCleanFilter
Air handling unit
  • SIBER DF EVO
  • SIBER DF EVO2
Filter dimensions139x175x48
Class EN779F7+G4
Class ISO16890ePM1 70%
Protection levelHigh: fine particles, dust, pollen, mold spores, combustion particles, smog particles, insecticide dust.
Quantity of filters1
Advantages
  • Maximum protection – ePM1 70% removes up to 40% more smog, pollen and fine dust than standard filters (50–60%).
  • Made in the EU – reliable quality and strict safety standards
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
Manufacturer product number
  • DFFF7
  • DFFG4F7
  • DFFF9
  • DFFG4F9
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4. Additional tips from installers

  • For city centres – use F7 or higher class filters, as urban air is polluted not only during the heating season but also due to vehicle emissions.
  • In valleys or low-lying areas – air circulation is weaker in winter, and smog tends to linger longer, so choose F7 or activated carbon filters.
  • If your filters clog too quickly – this usually indicates excess coarse dust from nearby construction or gravel roads. Install a pre-filter box with a cheaper G4 filter to protect the main one. Some ventilation unit manufacturers such as Blauberg, Brofer, Maico, Recom and Vallox already include a G4 filter before the F7 supply filter. Zehnder also offers an external preheater box with an integrated primary filter.
SAVE VSR 500 (PF) F7+M5 Filter set

SAVE VSR 500 (PF) F7+M5 Filter set (Efficient)

Price 23.45 €

Ex VAT: 23.45 €

Manufacturer of MVHRSystemair
ManufacturerCleanFilter
Air handling unitSAVE VSR 500 (PF)
Filter dimensions
  • 487x243x24
  • 487x288x24
Class EN779F7+M5
Class ISO16890ePM1 70%
Protection levelHigh: fine particles, dust, pollen, mold spores, combustion particles, smog particles, insecticide dust.
Quantity of filters2
Advantages
  • Maximum protection – ePM1 70% removes up to 40% more smog, pollen and fine dust than standard filters (50–60%).
  • Made in the EU – reliable quality and strict safety standards
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
Manufacturer product number
  • 25212
  • 317693
Remarksℹ️ Dimensions are provided according to the Systemair standard (with gasket). Actual filter dimensions without the gasket may differ slightly. The filter is matched to your unit model.
VALLOX 110 SE/MV filter set No 22

VALLOX 110 SE/MV / ValloPlus 350 SC/SE/MV F7+2xG4 Filter set (No....

Price 13.41 €

Ex VAT: 13.41 €

Manufacturer of MVHRVALLOX
ManufacturerCleanFilter
Air handling unit
  • VALLOX 110 SE
  • VALLOX 110 MV
  • ValloPlus 350 SC
  • ValloPlus 350 SE
  • ValloPlus 350 MV
Filter dimensions
  • 248x230
  • 248x230x96
  • 400x260
Class EN779F7+2xG4
Class ISO16890ePM1 70%
Protection levelHigh: fine particles, dust, pollen, mold spores, combustion particles, smog particles, insecticide dust.
Quantity of filters3
Advantages
  • Maximum protection – ePM1 70% removes up to 40% more smog, pollen and fine dust than standard filters (50–60%).
  • Made in the EU – reliable quality and strict safety standards
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
Manufacturer product number3354200
Paul Novus 300/450 1xF7/AC aktyvuntos anglies filtras (Kvapų)

Paul Novus 300/450 1xF7/AC Activated carbon filter (Odor)

Price 15.78 €

Ex VAT: 15.78 €

Manufacturer of MVHRPaul
ManufacturerCleanFilter
Air handling unit
  • Paul Novus 300
  • Paul Novus 450
Filter dimensions180x475x50
Class EN779F7/AC
Class ISO16890ePM2.5 60%
Protection levelParticles and odors: fine particles, dust, pollen, mold spores, combustion particles, volatile particles, NOx, O3 gases.
Quantity of filters1
Advantages
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
  • Absorbs volatile particles (odors) and harmful gases as NOx, O3, etc.
  • Made in the EU – reliable quality and strict safety standards
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
PAUL/Zehnder ISO-BOX DN160 1xG4 filtras (40 mm)

PAUL/Zehnder ISO-BOX DN160 1xG4 Filter (40 mm)

Price 6.87 €

Ex VAT: 6.87 €

Manufacturer of MVHR
  • Paul
  • Zehnder
ManufacturerCleanFilter
Air handling unit
  • PAUL ISO-BOX DN160
  • PAUL ISO-BOX DN160/2000W
Filter dimensions350x250x40
Class EN779G4
Class ISO16890Coarse 75%
Protection levelBasic: larger solid particles, dust, fluff.
Quantity of filters1
Advantages
  • German filtration material – hygienic (VDI 6022) and PFAS-free, for cleaner and safer air
  • ISO 16890 tested – performance verified by an accredited laboratory in Germany
  • Premium replacement filter – tested quality, airtight construction with fully bonded media, and reliable performance
  • Lower running costs – lower filter price, lower energy use, and usually longer time between replacements than higher-efficiency filters.
  • Made in the EU – reliable quality and strict safety standards
Manufacturer product number524000810
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Filter class comparison

Filter class Particle type Recommended environment
G4 (Coarse) Coarse dust, insects Clean environment, rural areas, no solid fuel heating nearby
M5 (ePM10) Medium dust, pollen Suburban or low-pollution areas
F7 (ePM1) Fine particles, pollen, soot City centres, industrial zones, or areas with solid fuel heating
Activated carbon Odours, smoke, VOCs Polluted or “smelly” environments with smoke or exhaust gases

Monitor the air quality in your area

Check real-time air pollution levels on the European air quality map. Even within the same city, air quality can vary significantly — sometimes a single neighbour’s chimney can noticeably affect how your ventilation system performs.

⚙️ Proper maintenance means a longer service life

Clogged filters put extra load on the fans, causing the unit to work harder, consume more electricity, and wear out faster. When air can no longer pass through dirty filters, it starts leaking through joints and gaps, bypassing filtration altogether.

A well-maintained ventilation unit can reliably serve you for 10–15 years.

Need help choosing the right ventilation filters?

Contact us – we’ll help you find the best solution for your ventilation unit.

📧 [email protected]
💬 Chat with us directly on cleanfilter.eu

Why choose CleanFilter

  • ✅ Wide selection of filters for the most popular ventilation unit models (Brink, Komfovent, Oxygen, Paul, Systemair, Zehnder, and more).
  • ✅ Seasonal filter options – G4, M5, F7, and activated carbon filters for every need.
  • ✅ Fast delivery and easy filter selection by ventilation unit model.
  • ✅ German-quality filter media and installer-recommended solutions.
Tags: activated carbon filter air filters for ventilation air handling unit filters cleanfilter g4 filter ventilation heat recovery filters hvac filter replacement MVHR filter ventilation unit filters |
Categories: AHU maintenance Indoor air quality