Wolter · 3 series
Car park and parking garage extract fans
For covered and underground car parks where the rules call for two independent fans or stages, Wolter builds double-stage AXG axial fans and units with two separate fans, in duct and cabinet versions.

German garage regulations and the VDI 2053 guideline call for extract by two independent fans or stages, for redundancy. Wolter builds two groups of equipment for this:
- AXG — an axial fan with two in-series, counter-rotating stages. Each stage has its own motor, so if one stops the other keeps running. Sizes 315–1600.
- Units with two separate fans: GAES/GADS duct units with backdraft dampers on the outlet, GAPF cabinets with plug fans and GAB cabinets with belt- or direct-driven fans.
The extract fans work with car park jet fans, which drive air and smoke towards the exhaust shaft, or with a duct network.
Series
Car-park extract fan series
AXG — two-stage axial fans
Two counter-rotating stages with separate motors: redundancy, high pressure and economical part-load operation.
GAES / GADS — twin-fan duct units
Rectangular duct unit with two separate fans and backdraft dampers for extract from smaller car parks, sizes 175–400.
GAB / GAPF — twin-fan cabinet units
Insulated cabinets with two fully separated fans: GAPF with plug fans, GAB with belt- or direct-driven fans.
Series comparison
| Series | Type | Airflow, m³/h | Pressure, Pa | Temperature rating |
|---|---|---|---|---|
| AXG | two-stage counter-rotating axial fan | — | — | −40…+40 °C; F300/F400 on request |
| GAES / GADS | twin-fan duct unit | — | — | — |
| GAB / GAPF | twin-fan cabinet unit | — | — | — |
Redundancy and energy saving
One AXG stage delivers about 65 % of the airflow at about 40 % of the power. Switching stages and pole numbers gives airflow steps of 100, 65, 50 and 33 %, and the fan can also run on a frequency inverter. The car park is ventilated at part load — for example on CO sensor signals — and full capacity is used only when needed.
Controls
Wolter’s garage fan catalogue describes the L-TG3 panel for two extract fans: redundant control and power circuits, automatic switchover on a fault, alternating duty, staggered start, inputs from a CO monitor, a door contact and the fire alarm, and monitoring of four fire dampers. It dates from the 2006 catalogue, so we confirm availability on request. In jet-fan car-park systems the fans are controlled from a PLC control cabinet.
How we select
We need the extract airflow, system resistance, redundancy and noise requirements, the installation location and, if the fan is part of the car park smoke extraction system, the required fire rating. AXG suits high airflow and high pressure; twin-fan units suit smaller car parks with ductwork.
Applications
Where they are used

Car park ventilation and smoke control
Jet-fan systems for underground and enclosed car parks: CO-controlled ventilation and fire smoke control without ductwork.
Learn moreSmoke exhaust and smoke control
F300/F400 smoke exhaust fans to EN 12101-3 for car parks, malls, atria and plant rooms, with design and CFD.
Learn moreResidential complex ventilation
One supplier for all ventilation in a residential complex: Wolter car-park jet fans plus Himpel apartment ERVs and fans.
Learn moreFAQ
Frequently asked questions
Why does an extract fan need two stages?
Two stages with separate motors provide redundancy: if one stops, the other keeps extracting at about 65 % of the airflow. The stages also allow economical part-load operation.
Can AXG be installed vertically?
Yes. AXG can be mounted horizontally or vertically; the manufacturer offers arrangements S, SU, SO, D, DU and DO.
Are these fans suitable for smoke exhaust?
Wolter’s operating instructions describe F300/F400 high-temperature versions of the AXV and AXG axial fans; we confirm the class for the required size at selection. The GAES, GAPF and GAB twin-fan units have no fire rating and are intended for normal extract.
Does Wolter make induction fans?
There is no separate induction fan range in the Wolter programme. In car parks with low ceilings this role is covered by the JFC centrifugal jet fan, from 221 mm high.
Need equipment selection or a system design?
Send us the layouts or the brief — we will prepare a selection, a calculation and a quotation.