Because polyester fabric is very strong you should wash the covers in the washing machine.
Can polyester be washed in washing machine. What you should mind when Washing linen. However you should defer to the washing instructions on the label. Use gentle setting and lowmid dryer heat or hang dry.
Most polyesters can be machine washed on a warm setting. Polyester easily develops static cling so always use either fabric softener in the washing machine or a dryer sheet. To do it at home only a few key polyester washing instructions are required.
The optimum washing temperature at which nothing can go wrong however is 40 degrees. Can Polyester be washed at 90 degrees. As with most synthetic rug fibers polyester rugs are machine washable.
While you can wash polyester in temperatures up to 230ish boiling water will kill the germs and bacteria just as easily. Also the washing machine can distort the fibers cause puckers and other damage. This will ensure that all stains are removed from the garment before they set into the fibers.
I agree it depends on the fabrication such as if it is designed to have a particular finish. Turn polyester-knit garments inside out before washing to prevent snags. This detergent you need for Polyester.
Always check the fabric care label particularly since polyester is generally combined with all kinds of fabrics. Note however that the information on the manufacturers label. What temperature does polyester melt.