Stop Hot Air Links
Check door gaskets and structural cracks. Even a small crack in the lower or pressure side of a bulk barn allows large quantities of heat to escape. In many instances, air leaks between the barn walls and the concrete pad or foundation go unnoticed and unrepaired. A 1/4-inch crack 15 feet long between the pad and the building may lose as much as 10% of the air and heat.
Ventilate Only Enough to Hold the Humidity Down
The wider the vent opening, the more fuel is required. Open the vent or fresh aire damper only enough to hold the humidity down to the proper level (100 degrees F to 105 degrees F wet bulb temperature during leaf drying and 105 degree F to 100 F wet bulk temperature during stem drying). Don't guess, use a wet bulb thermometer.
Well-insulated walls, roofs and floors may save as much as 75 gallons of fuel per cure. Often the pay-back time for the cost of bulk barn insulation is as short as three years. Insulation should be carefully applied in such a way as to prevent it being torn off and mixed with the cured tobacco.
Tune Up the Burner, Fan and Controls
Both oil and gas burners require periodic maintenance and adjustment for efficient operation. Fuel dealers usually have the proper tools and know-how for this job. Fan belts should be properly tightened and lubricated and the thermostats should be calibrated with a good quality alcohol or mercury thermometer at the start of every curing season.
Use a Wet Bulb Thermometer
Guessing at the humidity in the barn can lead to severe curing problems if its too high or waste valuable curing fuel if it is too low. Either way you lose. Wet bulb thermometers are cheap and easy to use.