How To Use An Air Conditioning Fan

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1 Venting Rule of Thumb 1x300x300 vent / 500llsec or per 1000 cfm Aeration for Profit How Much Air do I Need??? Aeration requires the correct Quantity and Quality of air for Success Two F370 Fans in an 80 tonne silo would generate 4.75 litres air/second /tonne in cereal grains!remember! The effectiveness of Aeration Maintenance, Cooling or Drying is not determined by Quantity of air alone. Aeration Management MUST take into account Air Temperature & Relative Humidity, Grain Type & Moisture. Final use of grain also influences Aeration Strategies.

2 Aeration Fans Air-flow & Pressure Conversions Air-flow Rate Common Units:- l/sec ( litre/sec ) cfm(cubic-ft/min) ; m 3 /hr (cubic-metre/hr) l/sec x 2.1 = cfm cfm x 0.47 = l/sec l/sec x 3.6 = m 3 /hr m 3 /hr x 0.28 = l/sec Pressure Common Units:- Pa (Pascal) ; mbar (millibar) inch WG ( inch Water-Gauge; inch H 2 0 ) inch-wg x 250 = Pa Pa x = inch H 2 0 inch-wg x 2.5 = mbar mbar x 0.4 = inch-wg Pa x 0.01 = mbar mbar x 100 = Pa - All Conversions are Approximate - Fan Model F kW F kW B kW B kW B kW B kW DF kW Typical Fan Air Flows -Cereal Grain- (varies with depth) Pa (1.5 H 2 O) Pa (2.5 H 2 O) Pa (2 H 2 O) Pa (1.5 H 2 O) Pa (3 H 2 O) Pa (3 H 2 O) Pa (4 H 2 O) -Canola - (varies with depth) Pa (2 H 2 O) Pa (4 H 2 O) Pa (3.5 H 2 O) Pa (3 H 2 O) Pa (6 H 2 O) Pa (6 H 2 O) Pa (6 H 2 O) GENERAL GUIDANCE ONLY - Fan models & performance may change Factors which affect air flow include Grain type/variety; GRAIN DEPTH (back-pressure); Trash in Grain; Moisture Content & Exhaust Air Venting

3 Equilibrium Moisture Content (EMC) of Grain Relative Humidity (RH) is a measure of how much moisture (water) is present in air compared to the MAXIMUM amount that could be held. For Example. If a sample of air (at a particular temperature) contains 25 units of water and a maximum amount that could be held is 50 units then the air is at 50% RH. When the Relative Humidity (RH) of air & the Moisture Content (MC) of grain are at equilibrium then no movement of moisture occurs between the air and grain. Then air and grain are at their ERH (Equilibrium Relative Humidity) and EMC (Equilibrium Moisture Content) points respectively. If the RH of air surrounding grain is less than the ERH value then moisture moves from the grain to air. If the RH of air surrounding the grain is higher than the ERH value then moisture moves from the air to the grain. For General Guidance Actual values may vary from those shown. Factors that affect ERH and EMC values include temperature, grain variety, location and weather grain is loosing or absorbing moisture. Information is typical for temperatures between 25ºC to 30ºC Equilibrium Moisture Content (%) Relative Humidity Sorghum Barley Maize Wheat Soybean Sunflower 90% % % % % % ºC to 30ºC The table demonstrates that air at 70% RH is in equilibrium with sorghum at 14%mc. This means that air with less than 70% RH has the potential to remove moisture from sorghum with a Moisture content of 14% or greater. The rate of moisture removal will generally be slow until the RH is well below equilibrium level

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5 Elevated Steel Cone Silos Folded Duct Aeration Systems Ground Operated Vents for Sealed Silos are available 3 Section Duct Kit complete with Fan Mounting Plate Fan can be mounted anywhere along the duct length Duct Segments in various lengths and sizes to provide correct air distribution for different silo models F370 Fan 0.37kw High Performance F650 Fan 1.5kw Available in 240 or 415 v Phosphine Matts can be used inside ducting on sealed silos Fan Units sized to provide correct air volumes for various silo models Position lowest point of duct 350mm from outlet Self Cleaning Modular Duct design fits flush with silo cone floor Round hole and Louvre Duct Options give operating flexibility Fan Sealing Kit option suits sealable silos High performance fan fits under cone for greater weather protection.

6 Flat Floor Silos Above Floor Tubular Duct Aeration Systems Duct Segments in various lengths and sizes to provide correct air distribution for different silo sizes Wall Transitions to suit various silo models Fan Units sized to provide correct air volumes for various silo models Tubular Ducting allows easy clean-down &support supports large grain depths. Fan sealing kit option suits sealable silos Wall transition engineered in heavy gauge metal for high strength and long life.

7 Temporary Grain Storage Aeration Portable SPEAR Aeration System Fan unit is supplied ready to plug in. Transition Section with robust fan connection and wind in tube section Tube length in grain approximately 1.8 metres Duct Section fabricated with flights to allow duct to be wound deep into the grain Typical Applications Tubular perforated duct section distributes air evenly in most seed and grain. High Capacity fan allows rapid heat and moisture movement by air. Spiral flighting makes it easier to screw tube into grain

8 Shed Aeration Above Floor Tubular Duct Systems Custom Designed Shed Systems End or Side Entry Fan & Duct Sets Duct Segments in various lengths and sizes to provide correct air distribution for different shed sizes Wall Transitions to suit various sheet profiles Twin Duct End Entry Shed Aeration System Fan Units sized to provide correct air volumes for various shed sizes Segmented Tubular Ducting fits together easily and supports large grain depths Heavy Duty Galvanized Fans Provide reliable air flow. Wall & Floor Transitions are supplied in heavy gauge metal for high strength and long life.

9 In-Ground Concrete Cone Silos Tubular Duct Aeration Systems Duct Segments in various lengths and sizes to provide correct air distribution for different silo sizes Wall Transitions to suit various silo models Fan Units sized to provide correct air volumes for various silo models Tubular Ducting allows easy clean-down &support supports large grain depths. Fan sealing kit option suits sealable silos Wall transition engineered in heavy gauge metal for high strength and long life.

10 Flat Floor Silos In Floor Duct Aeration Systems Duct covers available in various lengths and sizes to provide correct air distribution for different silo models. Wall Transitions matched to silo model and fan size Fan Units sized to provide correct air volumes for various silo models Removable trench covers allow easy clean down & support large grain depths. Fan sealing kit option suits sealable silos. Wall Floor transitions engineered in heavy gauge metal for high strength and long life.