Negative-Pressure Exhaust Fans
Large wall fans that pull air out of the house to keep the air fresh and temperature under control.

Climate Control · G02
Evaporative pads that cool incoming air in hot weather.
Sizes and configuration are customised to the project; details are agreed with you before quotation.
Cooling pads are made of corrugated cellulose. Water runs down the pad, and air pulled through it is cooled by evaporation. They are fitted at the end wall opposite the exhaust fans, and they work best in hot, dry weather.
Air pulled through wet pads is cooler.
Placed on the end wall so air crosses the house.
Works well where the air is hot and dry.
Typical reference values. Final dimensions, materials and configuration are customised to your project and confirmed with you before quotation.
| Characteristic | Description |
|---|---|
| Material | Corrugated cellulose pad |
| Typical thickness | 100 mm or 150 mm (reference) |
| Typical height | About 1.0–2.0 m (reference) |
| Water supply | Pump, pipe, tank, overflow |
| Frame | Galvanised or aluminium |
| Customisation | Yes. Sizes, materials and configuration are adapted to the project. |
| Installation | Supported by HNYZ installation teams; scope agreed per project. |
| Packing and transport | Packed for sea or road shipping; method agreed per order. |
| Warranty | Agreed per project. |
| Certificates | Please ask for the documents required in your market. |
Why HNYZ Group
They help less when the air is already humid. We recommend other measures there.
Regularly; the water quality matters. We give maintenance advice.
From the house volume, pig number and peak outside temperature. We calculate the airflow and propose the fan count.
In hot climates, pads cool incoming air by evaporation and are common. In cold climates, heating matters more.
Yes. Controllers can sound an alarm when temperature goes out of range, and monitoring can be added.
Houses need a plan for power cuts: alarms, a generator, or emergency openings. We discuss options with you.
Fan power is a major part of running cost. Variable-speed fans and good design can lower it.
No. Dimensions, materials and configuration are customised to your herd size, climate and local rules, and agreed with you before quotation.
They are typical reference values to help you compare. Final specifications are confirmed with you before quotation.
Our installation teams install and commission the equipment. The scope for each project is agreed in the contract.
Warranty terms depend on the equipment and are agreed per project in the contract.
Enquiry
Send us your herd size, site and timeline. We reply with a recommended configuration and a quotation.
What happens next
You send your project details
Herd size, site, land and target start date. Rough numbers are enough.
We reply with a layout and an equipment list
Our team reviews your requirements and proposes a configuration.
We agree the details with you
Sizes, materials and scope are confirmed before any quotation.
Large wall fans that pull air out of the house to keep the air fresh and temperature under control.
Wheeled coolers that add local cooling where it is needed.
Adjustable inlets that let fresh air in and guide it across the house.