There are a few key technologies available today that can increase your paint booth or prep-station’s energy efficiency. The first one we will cover is your heating system.
When it comes to the way your heat is produced, a direct fired heating system is the way to go. Instead of heating the air through a heat exchanger (which is pretty much like a radiator), the flame produced by the burner is in direct contact with the airstream leading into the spray booth or work area. Direct fired heat is almost perfectly efficient with an average of about 98-99% of the gas used being turned into useable heat. Indirect fired heating systems that use a heat exchanger and chimney stack, are only about 70% efficient at best. Below is a picture of the difference in the mechanicals of a direct fired heated spray booth and indirect fired heated spray booth. In the burner section of the “before” diagram, you will notice a large heat exchanger and a fume chimney. In a direct fire heating system, the heater is much smaller and needs no chimney. It allows much more airflow to pass through the burner, increasing the speed of temperature rise and also gives the workspace more airflow and less stress (static pressure) is placed on the intake fan.
Direct vs Indirect Fired Heat
The rendering above also shows the difference buying or converting to a paint booth with heat recycle can make in terms of your fuel efficiency. Especially in the paint booth’s bake cycle, the burner is producing large amounts of heat to bring the substrate up to curing temperature. It is very costly if your spray booth does not recycle that air. In a booth with heat recycle, up to 90% of that heat can be recycled past the burner so the substrate’s temperature can be maintained with minimal use of gas. Once the paint booth is up to temperature, the burner can almost shut off and still maintain the proper curing temperature. You can purchase a paint booth with direct fire and heat recirculation or if you have an existing heat system or the is no heat in your paint booth, these features can be installed as retrofits. Generally speaking, adding direct fire heat and a recycle system can save you anywhere from 30-60% in overall costs. Fuel costs are diminished and immediately and productivity can actually increase due to faster and more consistent temperatures.
Whether you are purchasing a new paint booth or retrofitting a new mechanical unit to an existing one, make sure you ask for both direct fired heating and heat recycling. It will save you thousands in energy costs!