1 If your microfiber is heavily-soiled, they may be boiled in water for up to 10 min and then laundered as usual. This helps to release grease and other dirt in the cloths.It is a good idea to boil your microfiber 3-4 times a year for 10 minutes.  Personally, I love what we have fondly dubbed the “Norwex Deep Clean“. It is to boil a pot of water, and REMOVE it from heat. Then add one scoop of Norwex Ultra-Power Plus Laundry detergent to dissolve in the hot water. Now place your Enviro cloths, Body Cloths, etc in this hot water, and let it set overnight. Then launder as usual.