Pet Dryers

Over view and Details

by Gregory Crisp, Double K Industries

Classic Reprint Article

The knowledgeable selection and proper use of dryers is one of the many important challenges a successful groomer faces today. Ironically, the initial purchase price of any dryer represents only a minor percentage of its “related costs.” The most substantial related cost of any dryer is labor. There are also direct operating costs, and costs related to maintenance as well as amortization or life expectancy of the dryer. While labor costs are much less pronounced for the cage dryer category, the principle holds nonetheless for all categories of dryers. Foundationally, it is important for groomers to recognize that their most precious asset is their time and to a lesser extent the time their employees spend working.

PetGroomer.com Magazine 86

October / December 2022

eGroomer Journal January / March 2014 Many shops have the equivalent of one 86 PetGroomer.com Publications employee drying most of the time. With a wage of only $13 an hour (plus taxes, insurance etc.) at five hours per day, six days per week the annualized cost would be $23,400. If the use of a more effective dryer would save only 10%, it would of course represent a $2,340 savings to the shop owner. More critically, if the owner is spending 20% of her or his time drying and a more effective dryer selection could save 10% of their time (presuming an eight hour day) the savings annually would be 250 hours or over five weeks! That is precious time that could be devoted to business development or other productive activities. SINGLE OR TWO MOTORS A common illustration of this principle is when a groomer selects a single motor forced air/high velocity dryer because of the lower cost as opposed to a two motor forced air dryer. Most reasonably effective two motor forced air dryers will dry animals about 30% faster than their counterpart single motor dryer. In this scenario the savings per employee would be $7,020 annually and/or the owners time saved would be 750 hours or over 15 weeks annually! Many times over the years groomers have asked me a trade shows about our single motor forced air dryer. Our counsel to them has always been that while we considered our product superior to all others, it was academic unless they absolutely could not afford a two motor dryer. Our position was and remains that if we gave them the dryer at no cost and replaced it at no cost whenever it became necessary that it would generally not make sense for them to use it. This was and is simply because of the critical labor saving advantages of the two motor dryers. It should be noted that the exception to this rule would be the groomer who just does small dogs or just a couple of dogs a day or truly cannot afford the more expensive dryer and intends to utilize the single motor dryer temporarily while they develop their business. Direct operating costs, while less critical, are still substantial. Most effective two motor dryers operate using about 15 amps of electricity at 120 V. This is equivalent to 1800 watts during operation. A kilowatt hour is equivalent to 1000 W for one hour of operation. So the two motor dryer uses 1.8 kW per hour of operation. At an average cost of electricity in the US of 13.3 cents per kilowatt hour the two motor dryer operating at five hours per day will cost $7,182 in electricity annually. There are measurable distinctions in drying time/performance between many (Continued on page 87)

similar products by different manufacturers in the marketplace. One important point here is that even modest differences in effectiveness can easily result in a product paying for its direct operating costs with a greater number of dogs dried and the resultant increase in revenue.

Dryer maintenance and product lifecycle are the least financially critical of the issues to consider but here again can still result in a superior product paying for itself in relation to a less effective product one or two times over in its lifecycle. BASIC DRYER PRINCIPLES

While some groomers research their dryer purchases diligently in advance and many by instinct or experience gravitate toward the most logical purchases an overview of some basic principles followed by some more nuanced detail may still be helpful. Firstly, while all dryers are air moving devices, the determinants of an effective dryer are: air volume, operational temperature/heat, air velocity/speed and pressure. The air volume a dryer produces is measured in cubic feet per minute (CFM). This principle may be readily understood by visualizing the quantity of cubes – 12 inches on each side (see illustration below) – a dryer could fill with air for each minute of operation. Operational temperature is defined as the increase in discharge temperature over ambient (room) temperature. Velocity is the speed of the discharge air measured in linear feet per minute

(FPM). Pressure is the amount of force pushing the air or that the discharge air exerts. The amount of pressure a dryer produces can be measured scientifically in “inches of water lift”. How far the air pressure can push or pull (by vacuum) water up a 1 inch diameter tube is the metric that defines its true “force”/ pressure. The “professional” categories of dryers have price ranges from about $100 to about $700 depending on quality, materials cost, the number and capacity

of motors, versatility, sophistication and manufacturers business models and strategies. FORCED AIR DRYERS

An important category in the industry is “forced air dryers.” These are invariably high pressure, moderate air volume and potentially high air velocity products. They typically have “commutator” type motor/fan assemblies which have relatively short life expectancies. Motor brushes generally last between approximately 500 hours and 1,400 hours of operation before requiring replacement. Replacement motor brushes generally last 20 to 30% less time than the preceding set with motor viability usually limited to three brush set changes. This results in motor life expectancies generally between about one thousand hours and 2,500 hours depending on intrinsic motor quality/ durability and compliance with proper brush changing techniques. Single motor dryers generally produce between 70 inches and 105 inches of water left. Two motor dryers generally produce between about 100 and 150 inches of water lift. This is important because air velocity is dependent on air pressure. Just because each of two motor fan assemblies produces 105 inches of water left does not mean you will get 210 inches of (water left) pressure out of the dryer. The two motor units nonetheless produce substantially more pressure than the single motor units as a whole. The forced air dryers generally produce between 60 and about 170 cubic feet of air volume per minute. A motor fan assembly that produces 124 cubic feet of air on a laboratory bench will not produce that much in a dryer because of “resistive elements.” The resistive elements include air filters, the dryer body, hoses and nozzles all of which the motor/ fan assemblies work to overcome thereby reducing the amount of air produced by the dryer as a whole. Forced air dryers are invariably hot or warm air dryers though most have no heating elements. This is because the air flows through the motor fan assemblies cooling the motors while heating the air simultaneously. A typical single motor dryer will raise the ambient temperature between 25 and 40°F. The typical two motor dryer will raise the ambient temperature between about 40 and 75°F. The elements described above allow some two motor dryers to produce warm air velocities of up to 20,000 ft./m, which is about 227 miles per hour while utilizing a narrow opening high velocity nozzle. Care must be taken of course when employing

high velocity air with eyes, ears and other sensitive areas on animals.

I would note here that some manufacturers have advertised their products for years as producing up to 58,000 ft./m. This is impossible as that would be air velocity of 659 mph and would be extremely destructive and dangerous in any case. This illustrates some of the challenges groomers face when researching products and making informed selections.

Having said this, the short motor life expectancies notwithstanding the two motor forced air dryers still represent the workhorses of the grooming industry for great penetration of thick or double coats, quick drying, stylistic flexibility and the labor and financial advantages referenced earlier. CAGE DRYERS

Cage dryers may represent the least understood and potentially most profitable category for groomers. They fall into three primary categories. The portable units are typically mounted on grooming, veterinary or travel cages. These are generally higher air volume dryers with the most wide-ranging temperature and air volume controls. Forced air dryers are also widely used with hoses attached and directed into the cages. “Squirrel cage” dryers, eGroomer Journal Copyright © 2011 Find A Groomer Inc. All rights reserved 89 PetGroomer.com Magazine www.petgroomermagazine.com Subscribe Free © 2022 Find A Groomer Inc All rights reserved

generally without heat are also commonly used with hoses directing air into the cages. The greatest misunderstanding and controversy regarding this category concerns heat/temperature. There is legislation in several states and cities prohibiting or limiting the use of this category of dryer. Much has been written about this and the issue of heated dryers in general and cage dryers specifically is a regular topic in social media. It is very important to understand that the use of regulated heat in any drying process is beneficial for animals being dried, reduces risk and speeds the drying process. With respect to cage dryers, the great majority of heated dryers used on cages have inadequately regulated heat. This allows heat accumulation in the cage and the risk of hyperthermia (high body temperature) and its associated consequences including the risk of animal death. The absence of heat in the cage drying process is almost always distressing for the animal and while not as dangerous as unregulated heat creates physiological risk nonetheless including the risk of death. A regular consequence of no heat cage dryers is hypothermia (low body temperature) because the evaporative process while the animal is being dried (Continued on page 90)

generally chills the animal and they commonly shiver uncomfortably in the background during the process. A reasonable illustration would be someone putting their wet head out the car window with an outside temperature of 74°F which would result in chilling. Again, while serious risk associated with no heat cage drying is substantially lower than unregulated heat cage drying, older animals or animals with heart conditions can still succumb to the chilling effects of the no heat cage drying process. Double K industries some years ago worked in collaboration with Dr. Joseph Bogarab to research the optimal temperature to maintain in a cage while drying animals. Dr. Bogarab wrote the standard and still most popular textbook on veterinary surgery in use today. Our work concluded that 107°F was the optimal maximum target temperature for cages in which animals are being dried with circulated air. This eliminates the risk of both hypothermia and hyperthermia and creates a comfortable “apparent temperature” for the animal being dried. It also substantially speeds the drying process over dryers with no heat. The dog’s body temperature generally ranges between 101 degrees Fahrenheit and 102.5°F. The 107°F maximum target cage environment was determined to be completely safe with an operational timer on the cage dryer even if an attendant forgot about or neglected the animal. Double K Industries model 560 cage dryer is the only portable cage dryer existing capable of achieving this objective. It is meaningful to note that virtually all forced air dryers used as cage dryers are using unregulated heat with associated hypothermic risk even though the dryers may have no heating element. Safe and effective cage drying represents one of the greatest opportunities for groomers to save labor and generate revenue. It can easily reduce drying related labor (costs) by half and many thoughtful groomers or already taking advantage of this equipment STAND DRYERS

Stand dryers have upright/elevated architecture generally with rolling bases that allow “hands-free” drying with animals on the tables. Increasingly, forced air dryers are mounted on stands with generally reduced motor related life expectancy but usually allowing increased versatility including high

velocity drying. “Conventional” stand dryers with induction motors as a rule have substantially longer motor related life expectancy because motor life is bearing dependent with motor bearings typically lasting 10,000 to 15,000 hours. Virtually all these units have heat either from heating elements or “through flow” motors in the forced air category. It is important to point out that there is a corollary between air volume and/or velocity and noise. All other things being equal a stand dryer producing twice the air volume will be considerably louder but dry the animal much more quickly. Some manufacturers have invested considerable effort to mitigate “acoustical insult” or excessive noise and a challenge for groomers is to select a product that dries quickly and effectively but is still relatively quiet in relation to air volume and velocity production. On balance, dryer selection is one of the most important decisions facing the discerning pet grooming professional and if pursued thoughtfully can result in direct and proportionate reductions in labor and increases in income. ◄