Professional Carwashing & Detailing

Choosing the right dryer

October 11, 2010
The best way to obtain the right drying system for an in-bay operation is to be as informed as possible. Being aware of the system’s capabilities, materials, decibels, energy usage, agents and general operation will allow you to make the most educated decision on which dryer will provide the greatest results. This, combined with proper machine maintenance, will produce a long lasting effective drying system for your company.

The basics
After the initial cost, a high quality product will provide a return on investment year after year, increasing bottom line profits. The ideal dryer utilizes low horsepower and is designed for efficiency and longevity.

Before purchasing a new system, make sure to ask the following questions:
  • How is this dryer different from the competition?;

  • How effective is this dryer? (Site visits are helpful); and

  • Is any after sales support offered?
Generally, dryers used for in-bay operations can be categorized as onboard or stand-alone systems. Onboard dryers are fixed to the wash equipment and move back and forth at a controlled pace utilizing the same area to dry the car as it’s washed. This type of dryer is effective for operations with minimal space since its footprint doesn’t require any extra room.

Subsequently, stand-alone dryers are installed separately from the wash equipment. This configuration allows another car to begin the wash process while the previous one is drying, and provides drip space for water shed prior to entering the dryer. As a result, stand-alone dryers prove to be more effective for faster turnaround while aiding in dryer efficiency.

When using stand-alone dryers, it is important to consider the control the customer has on the duration of the vehicle under the dryer. If the customers go through the cycle too fast, drying performance may be compromised. Often operators will install timers next to the dryers to indicate the best drive-through speed. Different dryers will have different drying times depending on their efficiency, so it is important to set the timer accordingly.

Materials
Carwashes are very demanding on their equipment since they expose them to continuous water flow, chemicals and agents necessary to the washing process. Textiles used to compose dryers determine the system’s maintenance, aesthetics, safety and ultimately equipment life.

When looking at the dryer’s impeller housing, safety becomes the most important point of concern. With the impeller’s rotation at 3,600 RPMs, any blower malfunctions may have severe consequences.

It is also important to consider the location of the motor blower assembly within the wash. Any type of equipment placed above a vehicle poses a potential safety risk. Operators need to ensure that their dyer assemblies are properly mounted and regularly check all overhead equipment. Another option is to place the dryer’s motor blower assemblies on the floor to remove this safety concern and allow for ease of maintenance.

Noise reduction
In order to protect employees, customers and the surrounding community, it is important to consider noise reduction precautions in carwashes. Industrial dryers are usually considered to be the loudest equipment in the washing process, with levels measuring from 75-100+ decibels. This becomes an issue when the Occupational Safety and Health Administration (OSHA) monitors noise levels anywhere at or above 85 decibels.

To resolve this problem, certain dryers come equipped with silencing packages. Some manufactures also offer aftermarket silencers that can be integrated with an existing system.

Energy efficiency
In recent months, there have been huge increases in oil, gas and coal prices, all of which are used in the generation of electricity. In turn, these escalations are reflected in the price the end user pays for their power. Operators should be aware of the direct relationship of the cost of operation per horsepower to kilowatt usage (1hp = 0.746 kilowatts).

Staggered starts, variable frequency drives (VFD) and other motor load control devices help minimize demand rates and improve energy efficiency between vehicles. In any case, operators should make sure the dryer is back to full power before the car enters the dryer so the system is able to operate at full capacity.

The best way to measure dryer performance is through air velocity. This does not necessarily mean using more horsepower for greater CFM discharge; instead it is the amount of force in which the air travels to the vehicle’s surface. Efficient impeller and discharge designs, such as nozzles and bags, increase the amount of velocity that reaches the vehicle, drying the car efficiently without consuming more energy.

Dryer agents
Even when using the best drying systems, operators may not always achieve desirable drying results. Often, it is the wash process that aids in the best outcome. Cleaning products work together and work best when pH balanced. When there is too much alkaline in the wash process, water tends to lay flat and sheet instead of breaking on the surface inhibiting the drying process.

When it comes to breaks in the wash process it’s not a question of drying the automobile faster, but more effectively. Breaks are open dry pockets on the vehicles surface which force water to stream off the car. This action reduces the water’s surface area resulting in less friction and allowing the natural force of gravity to aid in the drying process. In addition, water breaks allow the dryer’s blowers to force air under the water to effectively strip it from the vehicles surface.

Water breaks should not to be confused with beading, a situation where the water forms into many small droplets inhibiting the flow of water off of the vehicle resulting in less efficient drying. There are many variables that affect the balance of the wash process such as climate, humidity, season, regional air qualities and road surface conditions. Consulting with your regional supplier is recommended to assist you in making your system properly pH balanced to obtain the right chemical levels in the wash process allowing for the cleanest, brightest and driest results.

In the end, customers will respond to what they see. The most valued drying surfaces are the front windshield, front hood, driver’s side window, passenger side window; then the rear window, backseat passenger windows, and trunk. An effective dryer will proficiently dry these areas, utilizing minimal time and horsepower.


J.R. Klemmer began his career in the carwashing business after serving in the United States Air Force. From 1987 to present, J.R. has been associated with Proto-Vest, Inc., where he currently is vice president and general manager within their Glendale, AZ, office.