A ducted distribution system delivers air uniformly across the rack area. The fittings, dampers and diffusers page shows common duct layouts for herb-drying sheds.

Duct diameter depends on the number of collectors manifolded together. SVPro provides a duct sizing guide with each installation specification.

For installations adjacent to noise-sensitive areas (bedrooms, offices, care rooms), acoustic silencers on the supply duct are recommended. SVPro supplies compatible silencer models rated for the collector flow range.

A motorised back-draught damper closes when the collector fan stops (night, heavy cloud), preventing cold air from flowing backwards through the duct and into the building. It is a standard component in any installation with a long duct run.

Short flexible sections at the collector spigot are acceptable. Excessive flexible duct significantly reduces airflow.

In Australian climates, short exposed duct runs generally do not need insulation, but long exposed runs in alpine regions benefit from it.

A reduction fitting steps the duct diameter down from the manifold to a distribution branch. This maintains airflow velocity and minimises turbulence. SVPro snap-fit fittings include reducers matched to standard SVPro spigot and duct sizes.

SVPro motorised back-draught dampers operate on 24V. A step-down transformer from 240V mains is required. The controller output connects to the transformer, which powers the damper actuator.