Installation recomendations when retrofiting a barn
Service your barns to cure easy, nice tobacco with low fuel consumption.
Make sure your barn has good grounding. Consult your electrician and if necessary, replace old inefficient grounding with new, according to local regulations. Absence of correct ground is unsafe and will cause burner misfiring.
Check that you have appropriate electrical supply to your barns – size of main fuses, switches, and wiring.
Prevent air losses to your barns. Service your barn structure. Fix all loose sheets or plywood pieces at roof and barn’s sides. Close all gaps with appropriate acrylic sealer, silicone or foam. Paint foam after it matures. Paint any exposed and damaged polyurethane foam in order to avoid small particles getting on the tobacco.
Gaps in curing room and machine room’s upper and lower plenums will result in air leaks which will make Colouring difficult, may delay curing time, and will increase fuel consumption.
Prevent heat losses from your barn’s structure. Check that barn’s roof and insulation are in good condition & that the back sides of the barn (mainly at the upper and lower plenum) exposed to the outside conditions are insulated. If not, add appropriate insulation and cover with plywood or metal sheet to decrease heat losses to the atmosphere. Do not use exposed glassfibre mattress if it is not well protected with metal sheet or plywood.
Note : Heat losses will delay your cure and will increase fuel consumption.
Service your air exhaust dampers so they can move freely.
Service your boxes or racks so that when placed in the barn, they touch each other without leaving gaps. Note : Gaps of 1/3" between boxes may delay curing by one day, will increase fuel consumption by 30% and may cure tobacco of lower grade.
Service your curing room’s side rubber gaskets. Check that when racks or boxes are in the barn, there are no gaps to the side walls, or to the front doors, which will cause the air to bypass tobacco mass.
Prepare foam stripes (indicatively 8" x 8" x 9′) for closing the remaining gap between the boxes and front doors when curing so you can force the air to pass through the tobacco mass. The foam stripes can be made from mattress material wrapped with a cloth to prevent aging and transfer of small particles to the tobacco.
CAUTION: Do not use glassfibre insulation, or old aged mattress material, since air stream will transfer small undesired synthetic particles on the tobacco.
Service your water jets for conditioning. Check that your jets are well positioned, not spraying water on fan motor.
Gas pressure stabilizer, when firing Natural Gas (if you have experienced serious pressure fluctuations)
Antivibration Flexible joint is recommended
CAUTION : Follow your local regulations, call a qualified technician and follow burner’s manual before making connections & adjustments.
Take all necessary safety precautions when installing and running your VCU.
Gas may be explosive under certain conditions
Check at intervals for leakages in pipework and connections according to appropriate standards.
Check for correct connection and operation of all External Components.
Ground properly your Barn, Electrical panel, and Burner
Check for correct ground each season.
When starting your VCU
Check for correct fan rotation
Keep all side panels in place when operating. Do not open side panels if fan is still rotating
Do not open side panels until VCU disconnect is in OFF position.
A few words on Curing with VCU®
Curing technique with VCU® is practically the same as with the Direct Fired Units so the same Curing schedule can be followed. VCU® supplies the barn with large amounts of dry air. You may notice that you can cure your tobacco with smaller intake damper opening than what you are used to, since Direct Gas Firing produces also water vapors in the barn, so greater ventilation is required to drive out of the barn those extra vapors. Since greater ventilation is required, more btus are also required to cure the same tobacco in the same time margin. Indirect Gas Firing drives all combustion fumes (vapors too) outside the barn so smaller ventilation is required to cure the same tobacco in the same time margin. Above fact, VCU’s high efficiency and Ventobacco recommendations will help you get nice cures with the lowest possible fuel consumption.
VCU®(2K)is the most efficient and time proven Indirect Fired Curing Unit all around the world designed to exhaust combustion gases outside the barn with maximum efficiency, trouble free long lasting operation and the lowest possible fuel consumption.
VCU’s large Heat Exchanger all built in high quality Stainless Steel is designed to exceed 90% net efficiency combined with VV’s pressure burner. With proper management your VCU’s® fuel consumption during curing will be the same or lower than Direct Fired Furnace’s consumption.
You may also notice that your VCU’s pressure burner is firing for longer with less stops (longer operating cycles) than your atmospheric burner.
This is because it is adjusted at lower Btus per hour output compared to the atmospheric burner.
So instead of firing lots of Btus (more than necessary) for short time then stop for a while (since the fired Btus are more than necessary) and keep repeating many cycles per hour, VCU’s burner is designed to fire less Btus but for longer time, repeating less cycles per hour.
Follow the Ventobacco recommendations to perfectly match your VCU’s® operation to your barn and save fuel taking advantage of VCU’s efficiency.