Setting up Polycool
|Moisture content of crop*||Grain ventilated by 1.1kw or Evolution fan||Grain ventilated by VBW9 fan||Storage depth||Maximum spacing for pedestal units||Minimum spacing for pedestal units|
|15% and below||250 tonnes||400 tonnes||2.5-3.5 m||Storage depth plus 100%||4 m|
Storage depth plus 75%
|18% +||100 tonnes||200 tonnes||5.1m||
Storage depth plus 50%
*Assumed crop temperature is 20°C
· If starting storage temperatures are above 25°c we would recommend increasing fan numbers by approximately 25%.
· For storage depths below 6m use VBW7 or Evolution fans and standard pedestals.
· For storage depths above 5m use VBW9 fans and Maxi Polycool pedestals if 3 phase electricity is available.
Once storage depths exceed 4.5 metres we would advise that each store is treated on its merits according to crop type, storage depth and condition of crop to be stored. If you are unsure please contact us.
Loading the store
Loading the store around Polycool must be done with care not to knock the unit over, please use the installation film at https://www.evansandpearce.com/grain-pedestals/. If grain is being bucketed or tipped into the store, it is crucial that the bottom 600mm of pipe is well covered so that it ‘anchors’ itself to the floor before any vigorous pushing or movement of crop occurs. If the store is being loaded from overhead, it is important to ensure the top of the pipe is blanked off so that the Polycool Pedestal does not fill with grain. The fan should never be placed onto the Polycool Pedestal until the unit is completely surrounded from top to bottom with crop.
When to run and move the fans
We always recommend that fans are run constantly (day and night) for the first month of storage even if ambient air temperature is not lower than that of the crop, the air movement through the crop is important to help it stabilise. If fans are not run in a newly harvested crop, storage temperatures will soon rise to dangerous levels and the natural air ways through the crop will become blocked.
Differential control units are available to govern fan running times during the autumn period and will ensure that fans run at the optimum period when the outside air temperature is significantly cooler than that of the crop.
Fans are usually rotated on a 2 to 3 day cycle however for best results, regular temperature checks should be taken with fans moved accordingly. In damp crops, should the user notice water dripping from the outlet of a fan, it is best to turn the fan to blow for at least 24 hours in order to expel any moisture from the immediate vicinity of the duct. To do this, the user can simply remove the fan from it’s position and place what would have been the outlet spigot onto the pipe. There is no need for any rewiring or change to fan configuration.
Caring for fans
We always recommend in the first instance that fans are installed under the scrutiny of a qualified electrician. Motors are prone to low voltage burn out. It is always essential that the fan is receiving sufficient voltage and that any extension cables are of the correct size to service the distance they cover.
Should damage be sustained to fans as a result of low voltage burn then the warranty will be void.
Hydor roof fans
As warm air is removed from crops, it is expelled into the free air space above the crop. For best results, this air should be replaced regularly. HYDOR fans are available for this purpose and can be specified upon request according to the dimensions of the roof space. Please contact us for help with any such specification.