You are here

Fan / Heater Unit

Model: B25 Fan/Heater

Key Features

  • To dry medicinal or aromatic herbs on a ventilated platform
  • Capacity - approximately 10kgs of dry plant per m2 per 24 hours
  • Propane or natural gas burners - heat exchanger option available
  • High performance, low noise backward curved centrifugal fan rotor
  • Designed to operate continuously without supervision
  • Direct drive for low maintenance/maximum efficiency


The fan/heater units are designed to work in conjunction with a perforated platform on which the wet crop is laid - to a depth of about 30 cm (depending on crop). The stem and leaf of any type of plant can be dried, as well as grains and roots. Very dense matter such as large roots can need a much slower drying time at a greater bed depth and a lower airflow.


High performance backward curved centrifugal fan impellor direct driven by electric motor ensures optimum efficiency and low noise. The automatic pressure jet burner - LPG or Natural Gas fired - is mounted in a furnace duct on inlet to fan. The control panel incorporates safety shutdown systems and digital thermometer for temperature control and display - including alarm functions. The unit is pre-wired and factory tested. The drying platform can be of very simple construction with concrete block walls supporting a framework of steel tubes on which are laid the perforated steel sheets. It is normally built by the grower's own labour- although bed materials can be supplied, as required.


The fan/heater delivers hot air at controlled temperatures (generally 40°C for most herbs) to the drying platform. In most cases the crop will be fully dry within 2 hours, at the end of the cycle the furnace is turned off so that the crop can be cooled. Greater fuel economy can be achieved by designing the installation so that in the latter stages of drying when the exhaust air is not saturated with moisture, a proportion of the waste heat can be recycled back into the fan furnace.