This month, we will delve into identifying drying problems in DRY CLEANING machines. How can you tell if you have a drying problem? The following is a list of common symptoms associated with problems in the dry cycle:
ABRUPT CHANGE IN SOLVENT CONSUMPTION
Solvent consumption is often measured in the pounds cleaned per gallon or per “drum” (50 gallons) of solvent and is referred to as solvent mileage. If you notice a spike in solvent purchases, or you are amongst the few who track your solvent consumption and notice a sharp decrease in solvent mileage, drying problems should always be suspect.
STRONG SOLVENT ODOR IN THE ENVIRONMENT
Before the stricter environmental regulations, there was almost always a strong solvent odor inside a dry cleaning plant. With the advent of modern machinery, the solvent odor should only be detectable when removing the garments after drying (I’ll probably get an argument on this, but I’m being realistic).
STRONG SOLVENT ODOR ON GARMENTS AFTER BEING REMOVED FROM MACHINE
There will almost always be a slight odor on the garments after removal at the end of the drying cycle. Please keep in mind that the following testing is subjective. The sense of smell is desensitized by overstimulation. If you want to do a sniff test, grab a sport jacked and hold the garment at arm’s length for about 5 seconds. Then shake it for 3 seconds and sniff the surface (not a shoulder pad). For Perc systems, if there is any odor at all, it should be very slight; with DF2000 or its derivatives and for Green Earth, a slight odor is OK; for K4 (Solvon), there will be a slightly sweet odor which will dissipate rapidly. There are numerous causes for this condition which will be dealt with in detail next issue.
POOR GARMENT “HAND” OR FEEL
I’m not sure if the term “HAND” is used much anymore, but it means the texture or feel and appearance of the garment’s fabric. Suppose the fabric’s surface feels stiff or scratchy and the zippers are sticky. In that case, this could indicate either over-drying (drying too long or at too high a temperature) or a lack of detergent and/or sizing dissolved in the solvent during the wash cycle.
PILLING AND/OR SHRINKING
Pilling is the accumulation of compact clusters (Balls, to most of us) of fabric or lint on the garment’s surface. Shrinking is the reduction in size or distortion of the shape of a garment. Both of these disasters are usually caused by a combination of factors. For pilling excessive friction and overheating the garment, for shrinking excessive heat during drying, and for both, the presence of excessive moisture during the dry cycle will significantly boost these destructive processes.
At least four of the many causes of wrinkling are directly related to the dry cycle. FIRST- the lack of volume in the basket enables the garments to fall freely through the airflow, pure and simple. The volume of a garment is not always directly proportional to its weight. For example, ten pounds of silk garments take up far less volume than 10 pounds of comforters. Since weight is a far easier measure to work with, machinery manufacturers specify weight loading limits, which requires the dry cleaner to inject judgment into machine loading. SECOND- temperature of the air stream is critical. If the garments are overheated, wrinkles will be set in the fabric. That’s why a cool down while the basket is rotating is critical to avoiding wrinkles. THIRD-moisture plays a critical role in wrinkling. Excessive moisture during drying will enhance the production of wrinkles, especially on cotton and cotton blends. This is why the cotton pocket liners and waistbands in trousers are the first to be affected before shrinkage on woolens will occur. If you notice wrinkles in these areas beware, it’s likely shrinkage of woolens will not be far down the line. FOURTH- although this has nothing to do with the machine itself after the drying cycle is complete, allowing garments to remain in the basket of the dry cleaning machine without the basket rotating and leaving the garments in a clothes basket without hanging will allow wrinkles to set.
DRYING TIME IS TOO LONG
How long is too long for the dry cycle? Hard to say. When men were men and cars had fins, the machinery was of transfer type (separate washer/extractor and dryer). The dryers (also called reclaimers) had enormous volume-to-weight ratios. Because of this, dry times then were short and didn’t require devices to adjust the cycle length. Current 5th generation dry to dry machinery’s dry cycle time depends on machine design (airflow and internal drying monitoring methods), solvent type, garment mix, and loading. All that being said, the dry cleaner should be able to develop a baseline gained from experience for the average length of cycle time, incorporating the previous variables I listed. As a rule of thumb, about a 45-50 minute total cycle time for perc and a 60-80 minute cycle time for the lighter than water solvents. I’m sure there will be exceptions cited from these stated time frames.
GARMENTS ARE TOO HOT OR COLD AT THE END OF THE DRY CYCLE
Garment temperature is usually one of the best barometers of dry cycle efficiency. If the fabric and/or metal of the zippers or clasps are hot to the touch or the converse, there’s likely trouble in some components of the dry cycle apparatus. Here comes another rule of thumb. Garments should feel slightly warm to the touch (90-100 degrees F.).