Astberg AF Series Inline Fans: The Complete Buyer's Guide
If your bathroom fogs up after every shower, your kitchen holds onto cooking odors for hours, or your grow tent needs steady air exchange, an inline duct fan is usually the fix. Astberg's AF Series is built around one idea — strong airflow without the noise. This guide walks through the full AF lineup, what sets each model apart, and how to pick the right size for your space.
What Is the AF Series?
The AF Series is Astberg's range of silent mixflow inline duct fans — circular fans that sit inside the ducting rather than on a wall or ceiling. Because the motor and impeller live inline with the duct, these fans can be mounted anywhere along the pipe run: horizontally, vertically, or at an angle, and even in series with a second unit if you need extra static pressure.
Every fan in the range shares the same design philosophy:
Mixed-flow impeller — balances high air pressure with high volume, which is what lets these units stay quiet while still moving serious airflow.
Full ABS plastic body — lightweight, double-insulated, and strong enough for continuous duty.
Centre-mounted motor — the motor and impeller sit in the middle of the housing, so you can service or swap them without touching the ductwork.
Snap-joint fittings — push-fit connections that seal well and go together without special tools.
Flexible orientation — install at any point and any angle along the duct line.
The AF Series Lineup
Prices and stock availability change over time — always check the live collection page for current pricing.
AF150 — The Sweet Spot for Homes
The AF150 is the standout model in the range for residential use. It's a 150mm (6") duct fan rated at 530 m³/h (311 CFM), yet it runs at just 33 dB(A) — quiet enough for a bathroom, home office, or bedroom-adjacent laundry room. The housing is IP44 rated, meaning it's protected against dust and splashing water, and it weighs only 2.6 kg. This is the model most homeowners land on for bathroom extraction, kitchen backup ventilation, or small hydroponic tents.
AF200 — Stepping Up for Bigger Rooms
The AF200 moves into 200mm (8") duct territory, delivering 840 m³/h (494 CFM) at 352 Pa static pressure. It runs a dual-speed motor (2450/1950 rpm), giving 63 dB at high speed and a quieter 55 dB at low speed — handy if you want extra airflow on demand but a gentler setting for everyday use. At 4.9 kg, it's a natural step up from the AF150 for larger bathrooms, kitchens, or small commercial rooms that need more air changes per hour than a 150mm duct can comfortably deliver.
AF250 — Built for Bigger Commercial Runs
The AF250 sits in 250mm (10") ducting and pushes 1,405 m³/h (826 CFM), making it a strong fit for larger commercial rooms, multi-outlet duct systems, or spaces feeding several extraction points off one fan. It draws 225 W at 2,450 rpm and runs at 66 dB on high speed, dropping to 58 dB on low — again offering a quieter setting when full output isn't needed. At 7.5 kg it's heavier than the AF200 but still uses the same centre-mounted motor and snap-joint design for easy servicing.
AF315 — The High-Capacity Workhorse
At the other end of the range sits the AF315, a 315mm (12") fan built for spaces that need serious air changes — commercial kitchens, conference rooms, warehouses, or multi-room ducted systems. It pushes 2,206 m³/h (1,298 CFM) at up to 693 Pa of static pressure, drawing 275 W at 2,350 rpm. It's noticeably louder at 63 dB, which is expected at this airflow class, and is generally installed in plant rooms, ceiling voids, or anywhere noise isn't a primary concern.
AF100P and AF125 — Compact Options
The AF100P (100mm/4") and AF125 (125mm/5") sit below the AF150 in size and airflow, delivering 198 m³/h and 284 m³/h respectively. These suit smaller bathrooms, WCs, or shorter duct runs where a full 150mm system would be overkill.
Where the AF Series Fits
Residential: bathrooms, kitchens, laundry rooms, and utility spaces
Commercial: offices, conference rooms, hotel corridors, retail units
Specialty: hydroponic grow tents, warehouses, and general HVAC duct runs
Installation & Maintenance Notes
Because the AF Series uses a centre-mounted motor and snap-joint connections, installation is closer to "clip it into the duct" than a full ceiling-fan install. A few practical points:
The fan can be mounted in any orientation along the duct — you're not restricted to a specific up/down position.
For longer runs or higher resistance ducting, two AF units can be connected in series to boost overall pressure.
Because the motor assembly is removable without dismantling the ductwork, routine cleaning or motor servicing doesn't require cutting into the pipe.
Match the fan's duct size exactly to your existing ducting (100mm, 125mm, 150mm, or 315mm) — stepping down or up in size hurts efficiency and adds noise.
How to Choose the Right AF Model
Measure your existing duct diameter first. The fan has to match — there's no universal-fit option here.
Size for the room, not just the duct. A small ensuite is usually fine with an AF100P or AF125. A family bathroom or kitchen extraction point benefits from the AF150's higher CFM. Bigger rooms or higher-traffic spaces step up nicely to the AF200 or AF250, while large commercial areas, multi-outlet duct runs, or industrial spaces call for the AF315.
Weigh noise against airflow. The AF150's 33 dB(A) rating is close to a whisper; the AF315's 63 dB is noticeable, so it's better suited to plant rooms or spaces where people aren't sitting directly under it.
Check static pressure needs. Longer or more restrictive duct runs (multiple bends, filters, longer straight lengths) need more static pressure headroom — this is where the AF315's 693 Pa rating pulls ahead of the smaller models.
Frequently Asked Questions
What does "inline fan" mean, and how is it different from a ceiling exhaust fan? An inline fan sits inside the ducting itself, away from the room, rather than being mounted directly in a wall or ceiling opening. This keeps the motor noise further from the living space and lets you position the fan anywhere along the duct run — useful when the extraction point and the best place for the motor aren't the same spot.
Which AF model is best for a standard home bathroom? For most household bathrooms, the AF150 (150mm/6", 530 m³/h) hits the balance of strong extraction and low noise (33 dB(A)). Smaller or ensuite bathrooms with a 100mm or 125mm duct already installed can use the AF100P or AF125 instead.
Can Astberg AF fans be used for fresh air intake as well as exhaust? Yes. The mixflow impeller design supports both directions of airflow, so the same fan can extract stale or humid air out, or push fresh air in, depending on how it's plumbed into your ventilation system.
Are these fans energy efficient? Yes. The mixed-flow impeller is designed to deliver higher airflow and pressure without a proportional jump in power draw, which is why even the largest model in the range (AF315) draws a comparatively modest 275 W at full output.
Can I install an AF Series fan myself? The snap-joint fitting system is designed for straightforward installation without specialized tools, and many customers do fit them without a professional. That said, if you're unsure about duct sizing, electrical wiring, or fire/building code requirements in your area, it's worth having an electrician or HVAC installer confirm the setup.
What is the noise level of the AF Series fans? Noise scales with airflow capacity. The AF150 runs at 33 dB(A), close to background room noise. The AF200 and AF250 use dual-speed motors, so you get a quieter low-speed setting (55 dB and 58 dB respectively) as well as a higher-output setting (63 dB and 66 dB) when you need it. The high-capacity AF315 runs at a flat 63 dB. Choose based on how close the fan will be to occupied spaces and whether you need a low-speed option.
Do any AF Series fans have adjustable speed? Yes — the AF200 and AF250 both run dual-speed motors, giving you a high-output setting for peak extraction and a quieter low-speed setting for everyday background ventilation, without needing a separate speed controller.
Is the AF150 waterproof? The AF150 carries an IP44 rating, meaning it's protected against dust and splashing water from any direction — suitable for typical bathroom humidity and splash exposure, though it isn't designed for direct submersion or heavy water jets.
Can two AF fans be connected together? Yes. The AF Series supports series connection — installing two units along the same duct run to increase total static pressure, which helps on longer or more restrictive ducting where a single fan would lose effectiveness.
How long is the warranty or return window? Astberg backs its products with a manufacturer guarantee, and items purchased through the Astberg store can generally be returned or exchanged within 30 days of delivery. Always confirm current warranty terms on the product page before purchase, since policies can be updated.
Where can I see current pricing and stock for the AF Series? Pricing, stock availability, and any active discounts change over time, so the most accurate source is the live Astberg Inline Fans collection page.
