Do Misting Fans Really Work?

Misters Seem to be Gaining in Popularity and for Good Reasons

Misting fans can be a terrific and inexpensive alternative to more expensive methods of air cooling such as portable air conditioning units. The reason for this is the cooling power of the evaporation of water.

One gallon of water requires approximately 8300 BTU's/h to evaporate. Therefore, the surrounding air temperature drops relative to the amount of evaporation taking place. One ton of air conditioning relates to 12,000 BTU/h, so you can quickly see that when water evaporates rapidly the more efficient a misting system can be. This explains why evaporative cooling is very popular in regions where the humidity level is low. The following chart might be helpful in getting an idea of whether misting would benefit you in a significant manner:



That is not to say that the evaporative cooling effect is not useful in climates that might be described as humid. If used outdoors or in well ventilated spaces you can still get a 5 to 10 degree drop in temperature.

These products have become popular among athletes and can usually be seen on the sidelines of many sporting events (football in particular). Our firefighters use these fans to cool down their personnel when they exit a burning building and need to cool down rapidly as do people who work in industries where ovens and kilns are prevalent. Construction workers have found these to be of great benefit as well and there are now many models that have been made for use at home on the patio or deck.

COOLING A LARGE INDUSTRIAL SPACE CAN ACTUALLY SAVE YOU MONEY IN THE LONG RUN

THREE STEPS TO DEAL WITH SUMMER HEAT

Summer heat will be here soon and facility managers will need to assess their cooling and ventilation systems in preparation for the inevitable dog days. During that assessment it would be useful to review 3 proven steps to ensure that your efforts decrease the effect of outside temperatures by 15 to 20 degrees.

Step 1: Start at the Roof
The first step in a comprehensive cooling strategy would be an evaluation of the roof. Your roof is usually the largest source of heat within the facility unless you are working in a forgery or steel mill etc. Some roof types can see temperatures soar to over 185º F on a summer day. These temperatures are radiated down into the workspace. Even in facilities with high bay ceilings conduct this heat through the stratified air layers and raise overall temperatures all the way to the floor. The most effective means to combat this heat generation is to coat the roof surface with an elastomeric white thermal roof coating such as DuraCool. A 20 mil coating (2 coats) will keep the roof temperature within 2 degrees of ambient and prolong the life of the roof for 10 or more years while paying for itself in a very short time.

If you have an air conditioned facility your price savings will be enhanced due to high energy costs and the ability to allow your system to cycle on and off instead of operating continuously.

Step 2: Look at your Air Exchange
The second step in getting temperatures down is to ensure adequate ventilation for the size, shape, and type of facility being cooled. There are guidelines from agencies such as OSHA for a wide range of businesses. The idea here is to decide on the number of air changes that would be optimum for your industry and design the air supply and exhaust systems to accomplish this air turnover. Placement of these fans is important and you should consult with experts who can help you get the best results. The proper layout of fans is key for proper air exchange to take place. Besides the healthful effects of ridding your workspace of air pollution, smoke particulates and oil residue, this step supports good higher productivity from your employees by providing them with an ample amount of fresh air: sick days decrease, employees remain on the job and it is also proven that efficiencies are increased. This usually results in a payback that few calculate when upgrading their ventilation needs.

Step 3: Circulate Fresh Air within the Facility
The third step is an important one and though most people utilize fans in their facilities it is often haphazard at best: with fans competing against one another with uneven, inadequate cooling the invitable result. Utilizing the new Large Ceiling Fans to break up the stratified air and creating largely consistent air currents on the floor is a very good solution. This is an economical way to achieve general air circulation and if you use the new Horizontal Blowing versions of these fans you can push large volumes of air through aisles and mezzanines. The energy savings of these fans is obvious with 1 large fan replacing 30 or more conventional fans to cool the same area. During the winter months, these fans can be reversed and prevent the loss of usable warm air that accumulates at the ceiling. The lower thermostat settings can give you a very fast ROI (return on investment). Typical payback on these fans (depending on the severity of your summer and winter temperatures) can occur anywhere from 6 months to 2 years.

To conclude, these 3 steps will significantly improve your work environment while paying for themselves in a relatively short time. For hot spots and special workspaces that contain machinery or ovens that can generate their own heat, there are many products that can help such as portable evaporative coolers, air conditioners, workstation fans and misting fans.